diff --git a/package.json b/package.json
index e9a61ed21..c12d63a11 100644
--- a/package.json
+++ b/package.json
@@ -123,6 +123,7 @@
     "react-star-ratings": "^2.3.0",
     "react-switch": "^6.0.0",
     "react-tooltip": "^5.28.0",
+    "react-window": "^1.8.10",
     "redux": "^3.7.2",
     "redux-persist": "^5.10.0",
     "redux-thunk": "^2.3.0",
diff --git a/src/components/forms/promocode-form/__tests__/promocode-form.integration.test.js b/src/components/forms/promocode-form/__tests__/promocode-form.integration.test.js
index 05cf847f7..2d06f4545 100644
--- a/src/components/forms/promocode-form/__tests__/promocode-form.integration.test.js
+++ b/src/components/forms/promocode-form/__tests__/promocode-form.integration.test.js
@@ -1,8 +1,40 @@
 import React from "react";
-import { render, fireEvent, screen } from "@testing-library/react";
+import { render, fireEvent, screen, within } from "@testing-library/react";
 
 import PromocodeForm from "../index";
 
+// jsdom has no layout, so react-window's FixedSizeList won't render rows.
+// The modal under test uses it for the working-list view; mock it like the
+// manage-modal unit test does so the integration test can read the rows.
+jest.mock("react-window", () => {
+  // eslint-disable-next-line global-require
+  const React = require("react");
+  return {
+    __esModule: true,
+    FixedSizeList: React.forwardRef(
+      ({ itemCount, itemData, children }, ref) => {
+        const Row = children;
+        const visible = Math.min(itemCount, 10);
+        if (ref) {
+          ref.current = { scrollToItem: jest.fn() };
+        }
+        return React.createElement(
+          "div",
+          { "data-testid": "fixed-size-list" },
+          Array.from({ length: visible }, (_, i) =>
+            React.createElement(Row, {
+              key: i,
+              index: i,
+              style: {},
+              data: itemData
+            })
+          )
+        );
+      }
+    )
+  };
+});
+
 // jsdom does not implement scrollIntoView; polyfill so componentDidUpdate
 // (which calls scrollToError → firstNode.scrollIntoView) does not throw.
 window.HTMLElement.prototype.scrollIntoView = jest.fn();
@@ -489,6 +521,43 @@ describe("validate() — domain-authorized email-domain enforcement", () => {
     getByIdSpy.mockRestore();
   });
 
+  it("scrolls to the compact-mode wrapper when allowed_email_domains has > 50 entries (Codex A-fix regression)", () => {
+    // Codex pass-2 minor finding: A-fix added id="allowed_email_domains" to the
+    // compact wrapper, but no integration test exercised the FULL scrollToError
+    // path with > 50 entries. This test does. If a future refactor changes
+    // where scrollToError looks up the field, the unit tests at lines :545-:568
+    // still cover the static id presence — this test pins the end-to-end
+    // validate() → scrollToError → document.getElementById path in compact mode.
+    const getByIdSpy = jest.spyOn(document, "getElementById");
+    // 60 entries (> LARGE_DOMAIN_LIST_THRESHOLD=50) where at least one is
+    // malformed, so validate() fails and scrollToError fires.
+    const compactEntries = Array.from({ length: 59 }, (_, i) => `@e${i}.com`);
+    compactEntries.push("malformed");
+    const { container } = renderForm(
+      baseEntity({
+        class_name: "DOMAIN_AUTHORIZED_DISCOUNT_CODE",
+        allowed_email_domains: compactEntries
+      })
+    );
+    // Sanity-check we're in compact mode (compact-summary-count present —
+    // Manage List button is threshold-independent post-Tier 1.1 and no longer
+    // a valid compact-mode probe).
+    expect(
+      container.querySelector("[data-testid='compact-summary-count']")
+    ).toBeInTheDocument();
+    getByIdSpy.mockClear();
+    fireEvent.click(screen.getByRole("button", { name: /save/i }));
+    // scrollToError must have looked up the compact wrapper by id.
+    expect(getByIdSpy).toHaveBeenCalledWith("allowed_email_domains");
+    // And the lookup must have resolved (not returned null) — proves the id
+    // is actually present in the rendered DOM at large N.
+    const calls = getByIdSpy.mock.results.filter(
+      (r) => r.type === "return" && r.value !== null
+    );
+    expect(calls.length).toBeGreaterThan(0);
+    getByIdSpy.mockRestore();
+  });
+
   it("clears the .text-danger banner on plain typing after a failed save (regression — Codex review)", () => {
     const { container } = renderForm(
       baseEntity({
@@ -697,3 +766,100 @@ describe("DiscountBasePCForm — Apply to all Ticket Types audience restriction
     expect(helper.textContent).toBe(HELPER_KEY);
   });
 });
+
+describe("PromocodeForm — DOMAIN_AUTHORIZED bulk input (Tier 1)", () => {
+  // End-to-end through the row → modal → onApply → form state → onSubmit
+  // path. Does NOT mock the modal (unlike the row unit test) — exercises
+  // the actual ManageAllowedEmailDomainsModal component, which is why the
+  // file-level react-window mock is required (jsdom can't virtualize).
+  it("60 existing domains → compact summary → modal paste → Done → entity reflects merge", () => {
+    const seed = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const onSubmit = jest.fn();
+    const { container } = renderForm(
+      baseEntity({
+        class_name: "DOMAIN_AUTHORIZED_PROMO_CODE",
+        allowed_email_domains: seed
+      }),
+      { onSubmit }
+    );
+
+    // Above LARGE_DOMAIN_LIST_THRESHOLD (50) — chip wall is replaced by
+    // the compact summary + Manage List button.
+    expect(
+      container.querySelector("[data-testid='compact-summary-count']")
+    ).toBeInTheDocument();
+    expect(
+      container.querySelector("[data-testid='domain-chip-@e0.com']")
+    ).not.toBeInTheDocument();
+    expect(
+      container.querySelector("[data-testid='manage-list-button']")
+    ).toBeInTheDocument();
+
+    // Open the modal.
+    fireEvent.click(
+      container.querySelector("[data-testid='manage-list-button']")
+    );
+    expect(screen.getByTestId("manage-modal-textarea")).toBeInTheDocument();
+
+    // Paste mix: 3 valid net-new, 1 invalid, 1 dup-of-existing.
+    fireEvent.change(screen.getByTestId("manage-modal-textarea"), {
+      target: {
+        value: "@new1.com\n@new2.com\n@e0.com\nnot-a-domain\n@new3.com"
+      }
+    });
+    fireEvent.click(
+      screen.getByRole("button", {
+        name: "edit_promocode.manage_modal.add_button"
+      })
+    );
+
+    // Toast renders the raw i18n key in jest env (no translator); the
+    // interpolated numbers are not visible. Verify the tally via the
+    // working-list row count instead: 60 existing + 3 new = 63.
+    expect(screen.getByTestId("manage-modal-toast")).toHaveTextContent(
+      "edit_promocode.manage_modal.added_toast"
+    );
+    // FixedSizeList mock caps visible rows at 10; assert all 10 render.
+    const modalList = screen.getByTestId("fixed-size-list");
+    expect(within(modalList).getAllByTestId(/manage-modal-row-/)).toHaveLength(
+      10
+    );
+
+    // Commit via Done — onApply fires up through fireChange, parent
+    // handleChange updates entity.allowed_email_domains.
+    fireEvent.click(
+      screen.getByRole("button", { name: "edit_promocode.manage_modal.done" })
+    );
+
+    // The form's internal entity state should now hold the merged array.
+    // Trigger Save and inspect the entity passed to onSubmit. (react-bootstrap
+    // 0.31's animated Modal can stay mounted in jsdom because the exit
+    // transition never resolves, so the modal's buttons remain in the
+    // accessibility tree and shadow the form's Save. Query the Save input
+    // directly via its DOM selector instead.)
+    const saveBtn = container.querySelector(
+      "input[type=\"button\"].btn.btn-primary.pull-right"
+    );
+    expect(saveBtn).toBeInTheDocument();
+    fireEvent.click(saveBtn);
+
+    expect(onSubmit).toHaveBeenCalledTimes(1);
+    const submittedEntity = onSubmit.mock.calls[0][0];
+    expect(submittedEntity.allowed_email_domains).toHaveLength(63);
+    // Original entries preserved.
+    expect(submittedEntity.allowed_email_domains).toEqual(
+      expect.arrayContaining(["@e0.com", "@e59.com"])
+    );
+    // New entries appended.
+    expect(submittedEntity.allowed_email_domains).toEqual(
+      expect.arrayContaining(["@new1.com", "@new2.com", "@new3.com"])
+    );
+    // Invalid + dup NOT present.
+    expect(submittedEntity.allowed_email_domains).not.toContain("not-a-domain");
+    // No duplicate @e0.com (still only one instance).
+    const e0count = submittedEntity.allowed_email_domains.filter(
+      (d) => d === "@e0.com"
+    ).length;
+    expect(e0count).toBe(1);
+  });
+});
diff --git a/src/components/forms/promocode-form/forms/domain-authorized/AllowedEmailDomainsRow.jsx b/src/components/forms/promocode-form/forms/domain-authorized/AllowedEmailDomainsRow.jsx
index 1a92557d6..ec2c0248c 100644
--- a/src/components/forms/promocode-form/forms/domain-authorized/AllowedEmailDomainsRow.jsx
+++ b/src/components/forms/promocode-form/forms/domain-authorized/AllowedEmailDomainsRow.jsx
@@ -2,6 +2,14 @@ import React, { useState } from "react";
 import T from "i18n-react";
 import { validateAllowedEmailDomainEntry } from "../../../../../utils/methods";
 import { fireChange } from "./utils";
+import { LARGE_DOMAIN_LIST_THRESHOLD } from "./bulk-input-parser";
+import ManageAllowedEmailDomainsModal from "./ManageAllowedEmailDomainsModal";
+
+const typeOf = (entry) => {
+  if (entry.startsWith("@")) return "atDomain";
+  if (entry.startsWith(".")) return "tld";
+  return "email";
+};
 
 // Freeform chip input. Deliberately NOT openstack-uicore-foundation's
 // TagInput: that component wraps react-select's AsyncCreatable and fires
@@ -14,6 +22,7 @@ const AllowedEmailDomainsRow = ({
 }) => {
   const [draft, setDraft] = useState("");
   const [domainsError, setDomainsError] = useState("");
+  const [manageOpen, setManageOpen] = useState(false);
 
   const domains = Array.isArray(entity.allowed_email_domains)
     ? entity.allowed_email_domains
@@ -34,7 +43,11 @@ const AllowedEmailDomainsRow = ({
       );
       return;
     }
-    if (!domains.includes(trimmed)) {
+    const lowerTrimmed = trimmed.toLowerCase();
+    const alreadyPresent = domains.some(
+      (d) => d.toLowerCase() === lowerTrimmed
+    );
+    if (!alreadyPresent) {
       fireChange(handleChange, "allowed_email_domains", [...domains, trimmed]);
     }
     setDraft("");
@@ -63,113 +76,204 @@ const AllowedEmailDomainsRow = ({
     if (draft.length > 0) commit(draft);
   };
 
+  // Single-entry inline `+ add one` input. Declared once, mounted in BOTH
+  // branches (chip wall + compact summary) so the small-add affordance stays
+  // available at every list size — SDS L58/L69/L100/L186.
+  const inlineAddInput = (
+    <input
+      type="text"
+      data-testid="allowed_email_domains_input"
+      aria-label={T.translate("edit_promocode.allowed_email_domains")}
+      value={draft}
+      placeholder={
+        domains.length === 0
+          ? T.translate("edit_promocode.placeholders.allowed_email_domains")
+          : ""
+      }
+      onChange={(e) => {
+        setDraft(e.target.value);
+        setDomainsError("");
+        // Parallel-clear the parent validate()-path error so the
+        // .text-danger banner disappears as soon as the user starts
+        // editing — same UX every other field gets via index.js:114
+        // (newErrors[id] = "" inside handleChange). The chip input's
+        // onChange normally doesn't bubble to the parent (typing
+        // updates local draft only), so we synthesize a no-op array
+        // change to trigger the parent reset. Only fires when a
+        // parent error is currently set, so the cost (one extra
+        // setState) is paid only after a failed Save.
+        if (hasErrors("allowed_email_domains")) {
+          fireChange(handleChange, "allowed_email_domains", domains);
+        }
+      }}
+      onKeyDown={handleKeyDown}
+      onBlur={handleBlur}
+      style={{
+        border: 0,
+        outline: "none",
+        flex: 1,
+        minWidth: 120,
+        background: "transparent",
+        padding: 0
+      }}
+    />
+  );
+
   return (
-    <div className="row form-group" data-testid="allowed-email-domains-row">
-      <div className="col-md-12">
-        <label htmlFor="allowed_email_domains">
-          {T.translate("edit_promocode.allowed_email_domains")}&nbsp;
-          <i
-            className="fa fa-info-circle"
-            aria-hidden="true"
-            title={T.translate("edit_promocode.info.allowed_email_domains")}
-          />
-        </label>
-        <div
-          id="allowed_email_domains"
-          className="form-control"
-          style={{
-            minHeight: 38,
-            height: "auto",
-            display: "flex",
-            flexWrap: "wrap",
-            gap: 4,
-            alignItems: "center"
-          }}
-        >
-          {domains.map((d, idx) => (
-            <span
-              key={d}
-              className="label label-default"
-              data-testid={`domain-chip-${d}`}
+    <>
+      <div className="row form-group" data-testid="allowed-email-domains-row">
+        <div className="col-md-12">
+          <div
+            style={{
+              display: "flex",
+              alignItems: "center",
+              gap: 8,
+              marginBottom: 4
+            }}
+          >
+            <label htmlFor="allowed_email_domains" style={{ marginBottom: 0 }}>
+              {T.translate("edit_promocode.allowed_email_domains")}&nbsp;
+              <i
+                className="fa fa-info-circle"
+                aria-hidden="true"
+                title={T.translate("edit_promocode.info.allowed_email_domains")}
+              />
+            </label>
+            <button
+              type="button"
+              className="btn btn-default btn-xs"
+              data-testid="manage-list-button"
+              onClick={() => setManageOpen(true)}
+              style={{ fontWeight: "normal" }}
+            >
+              {T.translate("edit_promocode.manage_button")}
+            </button>
+          </div>
+          {domains.length > LARGE_DOMAIN_LIST_THRESHOLD ? (
+            <div
+              id="allowed_email_domains"
+              className="form-control"
               style={{
-                padding: "4px 8px",
-                display: "inline-flex",
-                alignItems: "center",
-                gap: 4,
-                fontSize: "0.95em"
+                minHeight: 38,
+                height: "auto",
+                display: "flex",
+                flexDirection: "column",
+                gap: 8,
+                padding: "8px 12px"
               }}
             >
-              {d}
-              <button
-                type="button"
-                aria-label={`remove ${d}`}
-                data-testid={`domain-chip-remove-${d}`}
-                onClick={() => removeAt(idx)}
+              <div>
+                <div
+                  data-testid="compact-summary-count"
+                  style={{ fontWeight: 600, fontSize: "1.05em" }}
+                >
+                  {T.translate("edit_promocode.large_list.summary_count", {
+                    n: domains.length
+                  })}
+                </div>
+                <div
+                  data-testid="compact-summary-type-mix"
+                  className="text-muted"
+                  style={{ fontSize: "0.9em" }}
+                >
+                  {(() => {
+                    const counts = { atDomain: 0, tld: 0, email: 0 };
+                    // eslint-disable-next-line no-restricted-syntax
+                    for (const d of domains) counts[typeOf(d)] += 1;
+                    return T.translate(
+                      "edit_promocode.large_list.summary_type_mix",
+                      counts
+                    );
+                  })()}
+                </div>
+                {domains.length > 0 && (
+                  <div className="text-muted" style={{ fontSize: "0.9em" }}>
+                    {T.translate("edit_promocode.large_list.summary_example", {
+                      entry: domains[0]
+                    })}
+                  </div>
+                )}
+              </div>
+              <div
                 style={{
-                  background: "transparent",
-                  border: 0,
-                  padding: 0,
-                  marginLeft: 4,
-                  color: "inherit",
-                  fontWeight: "bold",
-                  cursor: "pointer",
-                  lineHeight: 1
+                  display: "flex",
+                  alignItems: "center"
                 }}
               >
-                &times;
-              </button>
-            </span>
-          ))}
-          <input
-            type="text"
-            data-testid="allowed_email_domains_input"
-            aria-label={T.translate("edit_promocode.allowed_email_domains")}
-            value={draft}
-            placeholder={
-              domains.length === 0
-                ? T.translate(
-                    "edit_promocode.placeholders.allowed_email_domains"
-                  )
-                : ""
-            }
-            onChange={(e) => {
-              setDraft(e.target.value);
-              setDomainsError("");
-              // Parallel-clear the parent validate()-path error so the
-              // .text-danger banner disappears as soon as the user starts
-              // editing — same UX every other field gets via index.js:114
-              // (newErrors[id] = "" inside handleChange). The chip input's
-              // onChange normally doesn't bubble to the parent (typing
-              // updates local draft only), so we synthesize a no-op array
-              // change to trigger the parent reset. Only fires when a
-              // parent error is currently set, so the cost (one extra
-              // setState) is paid only after a failed Save.
-              if (hasErrors("allowed_email_domains")) {
-                fireChange(handleChange, "allowed_email_domains", domains);
-              }
-            }}
-            onKeyDown={handleKeyDown}
-            onBlur={handleBlur}
-            style={{
-              border: 0,
-              outline: "none",
-              flex: 1,
-              minWidth: 120,
-              background: "transparent",
-              padding: 0
-            }}
-          />
+                {inlineAddInput}
+              </div>
+            </div>
+          ) : (
+            <div
+              id="allowed_email_domains"
+              className="form-control"
+              style={{
+                minHeight: 38,
+                height: "auto",
+                display: "flex",
+                flexWrap: "wrap",
+                gap: 4,
+                alignItems: "center"
+              }}
+            >
+              {domains.map((d, idx) => (
+                <span
+                  key={d}
+                  className="label label-default"
+                  data-testid={`domain-chip-${d}`}
+                  style={{
+                    padding: "4px 8px",
+                    display: "inline-flex",
+                    alignItems: "center",
+                    gap: 4,
+                    fontSize: "0.95em"
+                  }}
+                >
+                  {d}
+                  <button
+                    type="button"
+                    aria-label={`remove ${d}`}
+                    data-testid={`domain-chip-remove-${d}`}
+                    onClick={() => removeAt(idx)}
+                    style={{
+                      background: "transparent",
+                      border: 0,
+                      padding: 0,
+                      marginLeft: 4,
+                      color: "inherit",
+                      fontWeight: "bold",
+                      cursor: "pointer",
+                      lineHeight: 1
+                    }}
+                  >
+                    &times;
+                  </button>
+                </span>
+              ))}
+              {inlineAddInput}
+            </div>
+          )}
+          <small className="form-text text-muted">
+            {T.translate("edit_promocode.captions.allowed_email_domains")}
+          </small>
+          {renderedError && (
+            <div className="text-danger" style={{ marginTop: 4 }}>
+              {renderedError}
+            </div>
+          )}
         </div>
-        <small className="form-text text-muted">
-          {T.translate("edit_promocode.captions.allowed_email_domains")}
-        </small>
-        {renderedError && (
-          <div className="text-danger" style={{ marginTop: 4 }}>
-            {renderedError}
-          </div>
-        )}
       </div>
-    </div>
+      <ManageAllowedEmailDomainsModal
+        show={manageOpen}
+        onHide={() => setManageOpen(false)}
+        onApply={(next) => {
+          setDomainsError("");
+          setDraft("");
+          fireChange(handleChange, "allowed_email_domains", next);
+        }}
+        existing={domains}
+      />
+    </>
   );
 };
 
diff --git a/src/components/forms/promocode-form/forms/domain-authorized/ManageAllowedEmailDomainsModal.jsx b/src/components/forms/promocode-form/forms/domain-authorized/ManageAllowedEmailDomainsModal.jsx
new file mode 100644
index 000000000..1f6184f34
--- /dev/null
+++ b/src/components/forms/promocode-form/forms/domain-authorized/ManageAllowedEmailDomainsModal.jsx
@@ -0,0 +1,173 @@
+import React, {
+  useState,
+  useEffect,
+  useMemo,
+  useRef,
+  useCallback
+} from "react";
+import { Modal } from "react-bootstrap";
+import { FixedSizeList } from "react-window";
+import T from "i18n-react";
+import { parseTextBlob, classifyEntries } from "./bulk-input-parser";
+
+const ROW_HEIGHT = 32;
+const LIST_HEIGHT = 320;
+
+const Row = React.memo(({ index, style, data }) => {
+  const entry = data[index];
+  return (
+    <div
+      style={style}
+      data-testid={`manage-modal-row-${index}`}
+      className="manage-modal-row"
+    >
+      {entry}
+    </div>
+  );
+});
+
+const ManageAllowedEmailDomainsModal = ({
+  show,
+  onHide,
+  onApply,
+  existing
+}) => {
+  const [working, setWorking] = useState([]);
+  const [draftText, setDraftText] = useState("");
+  const [toast, setToast] = useState(null);
+  const listRef = useRef(null);
+
+  // Intentionally depend only on `show`: snapshot `existing` when the modal opens
+  // and ignore subsequent prop changes — modal owns the working copy until Done/Cancel.
+  useEffect(() => {
+    if (show) {
+      setWorking(Array.isArray(existing) ? [...existing] : []);
+      setDraftText("");
+      setToast(null);
+    }
+  }, [show]);
+
+  const handleAddDomains = useCallback(() => {
+    const rows = parseTextBlob(draftText);
+    if (rows.length === 0) return;
+
+    const classified = classifyEntries({ raw: rows, existing: working });
+    const additions = classified.valid.map((v) => v.normalized);
+    const next = [...working, ...additions];
+
+    setWorking(next);
+    setToast({
+      added: classified.valid.length,
+      invalid: classified.invalid.length,
+      dup: classified.dupExisting.length + classified.dupInput.length
+    });
+    setDraftText("");
+
+    if (listRef.current && next.length > 0) {
+      listRef.current.scrollToItem(next.length - 1, "end");
+    }
+  }, [draftText, working]);
+
+  const handleKeyDown = (ev) => {
+    if (ev.key === "Enter" && (ev.metaKey || ev.ctrlKey)) {
+      ev.preventDefault();
+      handleAddDomains();
+    }
+  };
+
+  const handleDone = () => {
+    onApply(working);
+    onHide();
+  };
+
+  const handleCancel = () => {
+    onHide();
+  };
+
+  const toastText = useMemo(() => {
+    if (!toast) return null;
+    return T.translate("edit_promocode.manage_modal.added_toast", {
+      added: toast.added,
+      invalid: toast.invalid,
+      dup: toast.dup
+    });
+  }, [toast]);
+
+  const countText = T.translate(
+    "edit_promocode.manage_modal.configured_count",
+    {
+      n: working.length
+    }
+  );
+
+  return (
+    <Modal show={show} onHide={handleCancel} bsSize="large">
+      <Modal.Header closeButton>
+        <Modal.Title>
+          {T.translate("edit_promocode.manage_modal.title")}
+        </Modal.Title>
+      </Modal.Header>
+      <Modal.Body>
+        <div className="manage-modal-add-section" style={{ marginBottom: 12 }}>
+          <textarea
+            data-testid="manage-modal-textarea"
+            className="form-control"
+            rows={4}
+            value={draftText}
+            placeholder={T.translate("edit_promocode.manage_modal.add_helper")}
+            onChange={(ev) => setDraftText(ev.target.value)}
+            onKeyDown={handleKeyDown}
+          />
+          <button
+            type="button"
+            className="btn btn-primary"
+            style={{ marginTop: 8 }}
+            onClick={handleAddDomains}
+          >
+            {T.translate("edit_promocode.manage_modal.add_button")}
+          </button>
+        </div>
+        {toastText && (
+          <div
+            data-testid="manage-modal-toast"
+            className="alert alert-info"
+            style={{ padding: "6px 10px", marginBottom: 12 }}
+          >
+            {toastText}
+          </div>
+        )}
+        <div
+          className="manage-modal-count"
+          data-testid="manage-modal-count"
+          style={{ marginBottom: 4 }}
+        >
+          {countText}
+        </div>
+        <FixedSizeList
+          ref={listRef}
+          height={LIST_HEIGHT}
+          width="100%"
+          itemCount={working.length}
+          itemSize={ROW_HEIGHT}
+          itemData={working}
+        >
+          {Row}
+        </FixedSizeList>
+      </Modal.Body>
+      <Modal.Footer>
+        <button
+          type="button"
+          className="btn btn-default"
+          onClick={handleCancel}
+        >
+          {T.translate("edit_promocode.manage_modal.cancel")}
+        </button>
+        <button type="button" className="btn btn-primary" onClick={handleDone}>
+          {T.translate("edit_promocode.manage_modal.done")}
+        </button>
+      </Modal.Footer>
+    </Modal>
+  );
+};
+
+export default ManageAllowedEmailDomainsModal;
diff --git a/src/components/forms/promocode-form/forms/domain-authorized/__tests__/allowed-email-domains-row.test.jsx b/src/components/forms/promocode-form/forms/domain-authorized/__tests__/allowed-email-domains-row.test.jsx
index c0b51fa7c..3b6bedeb6 100644
--- a/src/components/forms/promocode-form/forms/domain-authorized/__tests__/allowed-email-domains-row.test.jsx
+++ b/src/components/forms/promocode-form/forms/domain-authorized/__tests__/allowed-email-domains-row.test.jsx
@@ -2,6 +2,32 @@ import React from "react";
 import { render, screen, fireEvent } from "@testing-library/react";
 import AllowedEmailDomainsRow from "../AllowedEmailDomainsRow";
 
+jest.mock("../ManageAllowedEmailDomainsModal", () => ({
+  __esModule: true,
+  default: ({ show, onApply, onHide, existing }) =>
+    show ? (
+      <div data-testid="manage-modal-mock">
+        <div data-testid="manage-modal-existing">
+          {JSON.stringify(existing)}
+        </div>
+        <button
+          type="button"
+          data-testid="manage-modal-mock-apply"
+          onClick={() => onApply(["@bulk1.com", "@bulk2.com"])}
+        >
+          mock apply
+        </button>
+        <button
+          type="button"
+          data-testid="manage-modal-mock-close"
+          onClick={onHide}
+        >
+          mock close
+        </button>
+      </div>
+    ) : null
+}));
+
 const baseEntity = (overrides = {}) => ({
   allowed_email_domains: [],
   ...overrides
@@ -301,3 +327,271 @@ describe("AllowedEmailDomainsRow", () => {
     ).toBe("");
   });
 });
+
+describe("AllowedEmailDomainsRow — compact summary + modal", () => {
+  it("renders chip wall when domains.length ≤ 50, with Manage List button always present (Tier 1.1)", () => {
+    const small = Array.from({ length: 50 }, (_, i) => `@e${i}.com`);
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: small })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      container.querySelector("[data-testid='domain-chip-@e0.com']")
+    ).toBeInTheDocument();
+    // Tier 1.1: Manage List button is threshold-independent; present at all counts.
+    expect(
+      container.querySelector("[data-testid='manage-list-button']")
+    ).toBeInTheDocument();
+    // Compact summary must NOT be visible at ≤ 50 — chip wall owns this range.
+    expect(
+      container.querySelector("[data-testid='compact-summary-count']")
+    ).not.toBeInTheDocument();
+  });
+
+  it("Manage List button present at count=0 (Tier 1.1 — empty-form bulk-paste entry)", () => {
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: [] })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      container.querySelector("[data-testid='manage-list-button']")
+    ).toBeInTheDocument();
+    expect(
+      container.querySelector("[data-testid='compact-summary-count']")
+    ).not.toBeInTheDocument();
+  });
+
+  it("boundary: chip wall at length=50, compact summary at length=51 (pins > vs >=)", () => {
+    const exactly50 = Array.from({ length: 50 }, (_, i) => `@e${i}.com`);
+    const { container: c50, unmount } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: exactly50 })}
+        handleChange={() => {}}
+      />
+    );
+    // Probe compact summary, not Manage List button (button is threshold-independent post-Tier 1.1).
+    expect(
+      c50.querySelector("[data-testid='compact-summary-count']")
+    ).not.toBeInTheDocument();
+    expect(
+      c50.querySelector("[data-testid='domain-chip-@e0.com']")
+    ).toBeInTheDocument();
+    unmount();
+
+    const exactly51 = Array.from({ length: 51 }, (_, i) => `@e${i}.com`);
+    const { container: c51 } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: exactly51 })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      c51.querySelector("[data-testid='compact-summary-count']")
+    ).toBeInTheDocument();
+    expect(
+      c51.querySelector("[data-testid='domain-chip-@e0.com']")
+    ).not.toBeInTheDocument();
+  });
+
+  it("renders compact summary when domains.length > 50 (Manage List button is always present)", () => {
+    const big = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: big })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      container.querySelector("[data-testid='domain-chip-@e0.com']")
+    ).not.toBeInTheDocument();
+    // i18n-react renders raw keys in jest env; the {n} interpolation is
+    // not visible, so we assert on the key wiring + button presence.
+    expect(
+      container.querySelector("[data-testid='compact-summary-count']")
+    ).toHaveTextContent("edit_promocode.large_list.summary_count");
+    expect(
+      container.querySelector("[data-testid='manage-list-button']")
+    ).toBeInTheDocument();
+    expect(
+      container.querySelector("[data-testid='manage-list-button']")
+    ).toHaveTextContent("edit_promocode.manage_button");
+  });
+
+  it("type-mix hint counts @domain / .tld / user@email correctly", () => {
+    // Total must exceed LARGE_DOMAIN_LIST_THRESHOLD (50) to render compact mode.
+    const mix = [
+      ...Array.from({ length: 46 }, (_, i) => `@d${i}.com`),
+      ".edu",
+      ".gov",
+      "user@example.com",
+      "x@y.com",
+      "z@w.com"
+    ];
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: mix })}
+        handleChange={() => {}}
+      />
+    );
+    const mixHint = container.querySelector(
+      "[data-testid='compact-summary-type-mix']"
+    );
+    // Raw key in jest env (no translator); the per-category numbers (46,
+    // 2, 3) are passed as i18n params and only visible at runtime. Pin
+    // the key wiring here.
+    expect(mixHint).toHaveTextContent(
+      "edit_promocode.large_list.summary_type_mix"
+    );
+  });
+
+  it("clicking Manage List opens the modal with current domains as existing", () => {
+    const big = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: big })}
+        handleChange={() => {}}
+      />
+    );
+    fireEvent.click(
+      container.querySelector("[data-testid='manage-list-button']")
+    );
+    expect(
+      container.querySelector("[data-testid='manage-modal-mock']")
+    ).toBeInTheDocument();
+    expect(
+      container.querySelector("[data-testid='manage-modal-existing']")
+    ).toHaveTextContent(JSON.stringify(big));
+  });
+
+  it("modal onApply bubbles via fireChange (handleChange called with new array)", () => {
+    const big = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const handleChange = jest.fn();
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: big })}
+        handleChange={handleChange}
+      />
+    );
+    fireEvent.click(
+      container.querySelector("[data-testid='manage-list-button']")
+    );
+    fireEvent.click(
+      container.querySelector("[data-testid='manage-modal-mock-apply']")
+    );
+    expect(handleChange).toHaveBeenCalledWith(
+      expect.objectContaining({
+        target: expect.objectContaining({
+          id: "allowed_email_domains",
+          value: ["@bulk1.com", "@bulk2.com"]
+        })
+      })
+    );
+  });
+});
+
+describe("AllowedEmailDomainsRow — case-insensitive single-entry dedup", () => {
+  it("rejects @ACME.COM when @acme.com is already present", () => {
+    const handleChange = jest.fn();
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: ["@acme.com"] })}
+        handleChange={handleChange}
+      />
+    );
+    typeAndCommit(container, "@ACME.COM");
+    const calls = handleChange.mock.calls.filter(
+      (c) => Array.isArray(c[0]?.target?.value) && c[0].target.value.length > 1
+    );
+    expect(calls).toHaveLength(0);
+  });
+});
+
+describe("AllowedEmailDomainsRow — inline + add one input present at every size (SDS L58/69/100/186)", () => {
+  it("renders the inline input when domains.length <= 50 (chip wall)", () => {
+    const small = Array.from({ length: 10 }, (_, i) => `@e${i}.com`);
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: small })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      container.querySelector("[data-testid='allowed_email_domains_input']")
+    ).toBeInTheDocument();
+  });
+
+  it("renders the inline input when domains.length > 50 (compact summary)", () => {
+    const big = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: big })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      container.querySelector("[data-testid='allowed_email_domains_input']")
+    ).toBeInTheDocument();
+  });
+
+  it("commits a single entry from compact mode via Enter (parity with chip-wall behavior)", () => {
+    const big = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const handleChange = jest.fn();
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: big })}
+        handleChange={handleChange}
+      />
+    );
+    typeAndCommit(container, "@new.com");
+    expect(handleChange).toHaveBeenCalledTimes(1);
+    expect(handleChange.mock.calls[0][0].target.value).toEqual([
+      ...big,
+      "@new.com"
+    ]);
+  });
+
+  it("case-insensitive single-entry dedup works in compact mode", () => {
+    const big = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const handleChange = jest.fn();
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: big })}
+        handleChange={handleChange}
+      />
+    );
+    typeAndCommit(container, "@E0.COM"); // dup of @e0.com case-insensitively
+    expect(handleChange).not.toHaveBeenCalled();
+  });
+});
+
+describe("AllowedEmailDomainsRow — scrollToError target present in both branches (Codex A2)", () => {
+  it("compact branch carries id='allowed_email_domains' so document.getElementById finds it", () => {
+    const big = Array.from({ length: 60 }, (_, i) => `@e${i}.com`);
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: big })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      container.querySelector("#allowed_email_domains")
+    ).toBeInTheDocument();
+  });
+
+  it("chip-wall branch still carries id='allowed_email_domains' (existing behavior, regression check)", () => {
+    const small = Array.from({ length: 10 }, (_, i) => `@e${i}.com`);
+    const { container } = render(
+      <AllowedEmailDomainsRow
+        entity={baseEntity({ allowed_email_domains: small })}
+        handleChange={() => {}}
+      />
+    );
+    expect(
+      container.querySelector("#allowed_email_domains")
+    ).toBeInTheDocument();
+  });
+});
diff --git a/src/components/forms/promocode-form/forms/domain-authorized/__tests__/bulk-input-parser.test.js b/src/components/forms/promocode-form/forms/domain-authorized/__tests__/bulk-input-parser.test.js
new file mode 100644
index 000000000..7e52da454
--- /dev/null
+++ b/src/components/forms/promocode-form/forms/domain-authorized/__tests__/bulk-input-parser.test.js
@@ -0,0 +1,150 @@
+import {
+  parseTextBlob,
+  normalizeEntry,
+  classifyEntries,
+  LARGE_DOMAIN_LIST_THRESHOLD
+} from "../bulk-input-parser";
+
+describe("LARGE_DOMAIN_LIST_THRESHOLD", () => {
+  it("is 50", () => {
+    expect(LARGE_DOMAIN_LIST_THRESHOLD).toBe(50);
+  });
+});
+
+describe("parseTextBlob", () => {
+  it("splits on newline, comma, tab, semicolon, and mixed separators", () => {
+    const raw = "@a.com\n@b.com,@c.com\t@d.com;@e.com";
+    const rows = parseTextBlob(raw);
+    expect(rows.map((r) => r.entry)).toEqual([
+      "@a.com",
+      "@b.com",
+      "@c.com",
+      "@d.com",
+      "@e.com"
+    ]);
+  });
+
+  it("trims whitespace and drops empty rows", () => {
+    const rows = parseTextBlob("  @a.com  \n\n@b.com\n   \n");
+    expect(rows.map((r) => r.entry)).toEqual(["@a.com", "@b.com"]);
+  });
+
+  it("preserves 1-based source row numbers", () => {
+    const rows = parseTextBlob("@a.com\n@b.com\n@c.com");
+    expect(rows[0].sourceRow).toBeGreaterThan(0);
+    expect(rows.map((r) => r.entry)).toEqual(["@a.com", "@b.com", "@c.com"]);
+  });
+
+  it("returns [] for non-string input", () => {
+    expect(parseTextBlob(null)).toEqual([]);
+    expect(parseTextBlob(undefined)).toEqual([]);
+    expect(parseTextBlob(123)).toEqual([]);
+  });
+});
+
+describe("normalizeEntry", () => {
+  it("preserves user-typed casing in normalized; dedupKey is lowercased", () => {
+    expect(normalizeEntry("User@ACME.com")).toEqual({
+      normalized: "User@ACME.com",
+      dedupKey: "user@acme.com",
+      autoPrefixed: false
+    });
+  });
+
+  it("auto-prefixes @ on bare domains; preserves casing of the rest", () => {
+    expect(normalizeEntry("ACME.com")).toEqual({
+      normalized: "@ACME.com",
+      dedupKey: "@acme.com",
+      autoPrefixed: true
+    });
+  });
+
+  it("auto-prefixes q.io (single-char SLD)", () => {
+    expect(normalizeEntry("q.io")).toEqual({
+      normalized: "@q.io",
+      dedupKey: "@q.io",
+      autoPrefixed: true
+    });
+  });
+
+  it("auto-prefixes a.co (single-char label, 2-char TLD)", () => {
+    expect(normalizeEntry("a.co")).toEqual({
+      normalized: "@a.co",
+      dedupKey: "@a.co",
+      autoPrefixed: true
+    });
+  });
+
+  it("does NOT auto-prefix entries that already start with @ or .", () => {
+    expect(normalizeEntry("@acme.com").autoPrefixed).toBe(false);
+    expect(normalizeEntry(".edu").autoPrefixed).toBe(false);
+  });
+
+  it("does NOT auto-prefix entries containing @ (likely user@domain)", () => {
+    expect(normalizeEntry("user@acme.com").autoPrefixed).toBe(false);
+  });
+
+  it("trims whitespace; returns empty fields for whitespace-only input", () => {
+    expect(normalizeEntry("   ")).toEqual({
+      normalized: "",
+      dedupKey: "",
+      autoPrefixed: false
+    });
+  });
+});
+
+describe("classifyEntries", () => {
+  it("classifies a single valid entry", () => {
+    const raw = parseTextBlob("@acme.com");
+    expect(classifyEntries({ raw, existing: [] })).toMatchObject({
+      valid: [expect.objectContaining({ normalized: "@acme.com" })],
+      invalid: [],
+      dupExisting: [],
+      dupInput: [],
+      autoPrefixed: []
+    });
+  });
+
+  it("case-insensitive dedup against existing", () => {
+    const raw = parseTextBlob("@ACME.COM");
+    const result = classifyEntries({ raw, existing: ["@acme.com"] });
+    expect(result.valid).toHaveLength(0);
+    expect(result.dupExisting).toHaveLength(1);
+  });
+
+  it("case-insensitive dedup within input (first wins)", () => {
+    const raw = parseTextBlob("@Acme.com\n@ACME.COM");
+    const result = classifyEntries({ raw, existing: [] });
+    expect(result.valid).toHaveLength(1);
+    expect(result.valid[0].normalized).toBe("@Acme.com");
+    expect(result.dupInput).toHaveLength(1);
+  });
+
+  it("classifies invalid entries (server-relaxed, client-strict)", () => {
+    const raw = parseTextBlob("@acme_corp.com\nuser@abc");
+    const result = classifyEntries({ raw, existing: [] });
+    expect(result.invalid).toHaveLength(2);
+    expect(result.valid).toHaveLength(0);
+  });
+
+  it("tracks auto-prefixed valid entries in both valid AND autoPrefixed lists", () => {
+    const raw = parseTextBlob("acme.com");
+    const result = classifyEntries({ raw, existing: [] });
+    expect(result.valid).toHaveLength(1);
+    expect(result.autoPrefixed).toHaveLength(1);
+    expect(result.valid[0].normalized).toBe("@acme.com");
+  });
+
+  it("realistic mixed input — 1 valid, 1 dupExisting, 1 dupInput, 1 invalid, 1 bare auto-prefix", () => {
+    const raw = parseTextBlob(
+      "@new.com\n@acme.com\n@ACME.com\nnot-a-domain\nbeta.io"
+    );
+    const result = classifyEntries({ raw, existing: ["@acme.com"] });
+    expect(result.valid.map((v) => v.normalized).sort()).toEqual(
+      ["@beta.io", "@new.com"].sort()
+    );
+    expect(result.dupExisting).toHaveLength(1);
+    expect(result.invalid).toHaveLength(1);
+    expect(result.autoPrefixed).toHaveLength(1);
+  });
+});
diff --git a/src/components/forms/promocode-form/forms/domain-authorized/__tests__/manage-modal.test.jsx b/src/components/forms/promocode-form/forms/domain-authorized/__tests__/manage-modal.test.jsx
new file mode 100644
index 000000000..92ca42329
--- /dev/null
+++ b/src/components/forms/promocode-form/forms/domain-authorized/__tests__/manage-modal.test.jsx
@@ -0,0 +1,158 @@
+import React from "react";
+import { render, screen, fireEvent, within } from "@testing-library/react";
+import ManageAllowedEmailDomainsModal from "../ManageAllowedEmailDomainsModal";
+
+// Mock react-window — jsdom has no layout, so FixedSizeList won't render rows.
+// Mock renders first 10 rows directly to match production's ~10-rows-visible cap.
+jest.mock("react-window", () => {
+  const React = require("react");
+  return {
+    __esModule: true,
+    FixedSizeList: React.forwardRef(
+      ({ itemCount, itemData, children }, ref) => {
+        const Row = children;
+        const visible = Math.min(itemCount, 10);
+        if (ref) {
+          ref.current = { scrollToItem: jest.fn() };
+        }
+        return React.createElement(
+          "div",
+          { "data-testid": "fixed-size-list" },
+          Array.from({ length: visible }, (_, i) =>
+            React.createElement(Row, {
+              key: i,
+              index: i,
+              style: {},
+              data: itemData
+            })
+          )
+        );
+      }
+    )
+  };
+});
+
+const onApply = jest.fn();
+const onHide = jest.fn();
+
+beforeEach(() => {
+  onApply.mockClear();
+  onHide.mockClear();
+});
+
+const openModal = (existing = []) =>
+  render(
+    <ManageAllowedEmailDomainsModal
+      show
+      onHide={onHide}
+      onApply={onApply}
+      existing={existing}
+    />
+  );
+
+describe("ManageAllowedEmailDomainsModal — Tier 1", () => {
+  it("renders title and Add Domains controls when shown", () => {
+    openModal();
+    expect(
+      screen.getByText("edit_promocode.manage_modal.title")
+    ).toBeInTheDocument();
+    expect(
+      screen.getByRole("button", {
+        name: "edit_promocode.manage_modal.add_button"
+      })
+    ).toBeInTheDocument();
+  });
+
+  it("paste 5 entries (1 valid, 1 dup of existing, 1 invalid, 1 bare auto-prefix, 1 blank) → toast tally", () => {
+    openModal(["@acme.com"]);
+    const textarea = screen.getByTestId("manage-modal-textarea");
+    fireEvent.change(textarea, {
+      target: { value: "@new.com\n@acme.com\nnot-a-domain\nbeta.io\n   " }
+    });
+    fireEvent.click(
+      screen.getByRole("button", {
+        name: "edit_promocode.manage_modal.add_button"
+      })
+    );
+    // i18n-react renders the raw key string in the jest env (no translator
+    // configured), so the toast/count text matches the key, not the
+    // interpolated copy. Verify the numeric outcome via the rendered row
+    // count, which reflects the actual working array.
+    expect(screen.getByTestId("manage-modal-toast")).toHaveTextContent(
+      "edit_promocode.manage_modal.added_toast"
+    );
+    expect(screen.getByTestId("manage-modal-count")).toHaveTextContent(
+      "edit_promocode.manage_modal.configured_count"
+    );
+    // 1 existing (@acme.com) + 2 new valid (@new.com, beta.io→@beta.io) = 3 rows
+    const list = screen.getByTestId("fixed-size-list");
+    expect(within(list).getAllByTestId(/manage-modal-row-/)).toHaveLength(3);
+  });
+
+  it("Cancel → onApply NOT called; onHide called", () => {
+    openModal(["@a.com"]);
+    fireEvent.click(
+      screen.getByRole("button", { name: "edit_promocode.manage_modal.cancel" })
+    );
+    expect(onApply).not.toHaveBeenCalled();
+    expect(onHide).toHaveBeenCalledTimes(1);
+  });
+
+  it("Done → onApply called with modal-scoped working array", () => {
+    openModal(["@a.com"]);
+    const textarea = screen.getByTestId("manage-modal-textarea");
+    fireEvent.change(textarea, { target: { value: "@b.com" } });
+    fireEvent.click(
+      screen.getByRole("button", {
+        name: "edit_promocode.manage_modal.add_button"
+      })
+    );
+    fireEvent.click(
+      screen.getByRole("button", { name: "edit_promocode.manage_modal.done" })
+    );
+    expect(onApply).toHaveBeenCalledWith(["@a.com", "@b.com"]);
+    expect(onHide).toHaveBeenCalledTimes(1);
+  });
+
+  it("Cmd+Enter inside textarea fires Add Domains", () => {
+    openModal();
+    const textarea = screen.getByTestId("manage-modal-textarea");
+    fireEvent.change(textarea, { target: { value: "@x.com" } });
+    fireEvent.keyDown(textarea, { key: "Enter", metaKey: true });
+    // Toast/count render the raw key in the jest env; verify the side
+    // effect via the row count instead of the interpolated number.
+    expect(screen.getByTestId("manage-modal-toast")).toHaveTextContent(
+      "edit_promocode.manage_modal.added_toast"
+    );
+    const list = screen.getByTestId("fixed-size-list");
+    expect(within(list).getAllByTestId(/manage-modal-row-/)).toHaveLength(1);
+  });
+
+  it("renders 1,400-entry list without crashing; virtualization shows only ~10 rows", () => {
+    const big = Array.from({ length: 1400 }, (_, i) => `@e${i}.com`);
+    openModal(big);
+    // Count text is the raw i18n key in jest env; the row-virtualization
+    // assertion below proves the modal handled the 1,400-entry input.
+    expect(screen.getByTestId("manage-modal-count")).toHaveTextContent(
+      "edit_promocode.manage_modal.configured_count"
+    );
+    const list = screen.getByTestId("fixed-size-list");
+    expect(within(list).getAllByTestId(/manage-modal-row-/)).toHaveLength(10);
+  });
+
+  it("snapshots existing on open — does NOT see parent state mutations after open", () => {
+    const { rerender } = openModal(["@a.com"]);
+    rerender(
+      <ManageAllowedEmailDomainsModal
+        show
+        onHide={onHide}
+        onApply={onApply}
+        existing={["@a.com", "@b.com", "@c.com"]}
+      />
+    );
+    fireEvent.click(
+      screen.getByRole("button", { name: "edit_promocode.manage_modal.done" })
+    );
+    expect(onApply).toHaveBeenCalledWith(["@a.com"]);
+  });
+});
diff --git a/src/components/forms/promocode-form/forms/domain-authorized/bulk-input-parser.js b/src/components/forms/promocode-form/forms/domain-authorized/bulk-input-parser.js
new file mode 100644
index 000000000..c79884145
--- /dev/null
+++ b/src/components/forms/promocode-form/forms/domain-authorized/bulk-input-parser.js
@@ -0,0 +1,79 @@
+import { validateAllowedEmailDomainEntry } from "../../../../../utils/methods";
+
+export const LARGE_DOMAIN_LIST_THRESHOLD = 50;
+
+const PASTE_SEPARATORS = /[\n,\t;]+/;
+
+export const parseTextBlob = (raw) => {
+  if (typeof raw !== "string") return [];
+  return raw
+    .split(PASTE_SEPARATORS)
+    .map((s, idx) => ({ entry: s.trim(), sourceRow: idx + 1 }))
+    .filter((r) => r.entry.length > 0);
+};
+
+const BARE_DOMAIN_RE =
+  /^[a-z0-9](?:[a-z0-9-]*[a-z0-9])?(?:\.[a-z0-9](?:[a-z0-9-]*[a-z0-9])?)+$/i;
+
+export const normalizeEntry = (raw) => {
+  const trimmed = (raw ?? "").trim();
+  if (trimmed.length === 0) {
+    return { normalized: "", dedupKey: "", autoPrefixed: false };
+  }
+  if (!trimmed.includes("@") && BARE_DOMAIN_RE.test(trimmed)) {
+    const normalized = `@${trimmed}`;
+    return {
+      normalized,
+      dedupKey: normalized.toLowerCase(),
+      autoPrefixed: true
+    };
+  }
+  return {
+    normalized: trimmed,
+    dedupKey: trimmed.toLowerCase(),
+    autoPrefixed: false
+  };
+};
+
+export const classifyEntries = ({ raw, existing }) => {
+  const existingKeys = new Set(
+    (existing ?? []).map((e) => String(e).toLowerCase())
+  );
+  const seenInInput = new Set();
+  const result = {
+    valid: [],
+    invalid: [],
+    dupExisting: [],
+    dupInput: [],
+    autoPrefixed: []
+  };
+
+  // eslint-disable-next-line no-restricted-syntax
+  for (const row of raw ?? []) {
+    const { normalized, dedupKey, autoPrefixed } = normalizeEntry(row.entry);
+    if (normalized.length === 0) continue;
+
+    if (!validateAllowedEmailDomainEntry(normalized)) {
+      result.invalid.push({ ...row, normalized });
+      continue;
+    }
+    if (existingKeys.has(dedupKey)) {
+      if (!seenInInput.has(dedupKey)) {
+        result.dupExisting.push({ ...row, normalized });
+        seenInInput.add(dedupKey);
+      } else {
+        result.dupInput.push({ ...row, normalized });
+      }
+      continue;
+    }
+    if (seenInInput.has(dedupKey)) {
+      result.dupInput.push({ ...row, normalized });
+      continue;
+    }
+    seenInInput.add(dedupKey);
+    result.valid.push({ ...row, normalized });
+    if (autoPrefixed) result.autoPrefixed.push({ ...row, normalized });
+  }
+
+  return result;
+};
diff --git a/src/i18n/en.json b/src/i18n/en.json
index f5a408eb3..6e09b6b04 100644
--- a/src/i18n/en.json
+++ b/src/i18n/en.json
@@ -1043,6 +1043,21 @@
     },
     "errors": {
       "allowed_email_domains_format": "Each entry must be an exact domain (@acme.com), a TLD suffix (.edu), or a full email address."
+    },
+    "manage_button": "Manage List",
+    "manage_modal": {
+      "title": "Manage Allowed Email Domains",
+      "add_helper": "Accepts domains (@acme.com), TLD suffixes (.edu, .gov), or exact emails (user@example.com).",
+      "add_button": "Add Domains",
+      "added_toast": "Added {added} · skipped {invalid} invalid · {dup} duplicates",
+      "configured_count": "Configured Domains ({n})",
+      "done": "Done",
+      "cancel": "Cancel"
+    },
+    "large_list": {
+      "summary_count": "{n} domains configured",
+      "summary_type_mix": "{atDomain} @domain · {tld} .tld · {email} user@email",
+      "summary_example": "e.g. {entry}"
     }
   },
   "discount_ticket": {
diff --git a/yarn.lock b/yarn.lock
index 81f28eeff..20eb24c71 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -979,7 +979,7 @@
     "@babel/plugin-transform-react-jsx-development" "^7.27.1"
     "@babel/plugin-transform-react-pure-annotations" "^7.27.1"
 
-"@babel/runtime@^7.1.2", "@babel/runtime@^7.10.0", "@babel/runtime@^7.11.2", "@babel/runtime@^7.12.5", "@babel/runtime@^7.15.4", "@babel/runtime@^7.17.8", "@babel/runtime@^7.18.3", "@babel/runtime@^7.18.6", "@babel/runtime@^7.20.13", "@babel/runtime@^7.25.7", "@babel/runtime@^7.26.0", "@babel/runtime@^7.28.6", "@babel/runtime@^7.5.5", "@babel/runtime@^7.7.2", "@babel/runtime@^7.8.7", "@babel/runtime@^7.9.2":
+"@babel/runtime@^7.0.0", "@babel/runtime@^7.1.2", "@babel/runtime@^7.10.0", "@babel/runtime@^7.11.2", "@babel/runtime@^7.12.5", "@babel/runtime@^7.15.4", "@babel/runtime@^7.17.8", "@babel/runtime@^7.18.3", "@babel/runtime@^7.18.6", "@babel/runtime@^7.20.13", "@babel/runtime@^7.25.7", "@babel/runtime@^7.26.0", "@babel/runtime@^7.28.6", "@babel/runtime@^7.5.5", "@babel/runtime@^7.7.2", "@babel/runtime@^7.8.7", "@babel/runtime@^7.9.2":
   version "7.29.2"
   resolved "https://registry.yarnpkg.com/@babel/runtime/-/runtime-7.29.2.tgz#9a6e2d05f4b6692e1801cd4fb176ad823930ed5e"
   integrity sha512-JiDShH45zKHWyGe4ZNVRrCjBz8Nh9TMmZG1kh4QTK8hCBTWBi8Da+i7s1fJw7/lYpM4ccepSNfqzZ/QvABBi5g==
@@ -8549,7 +8549,7 @@ memfs@^4.43.1:
     tree-dump "^1.0.3"
     tslib "^2.0.0"
 
-memoize-one@^5.0.0, memoize-one@^5.1.1:
+"memoize-one@>=3.1.1 <6", memoize-one@^5.0.0, memoize-one@^5.1.1:
   version "5.2.1"
   resolved "https://registry.yarnpkg.com/memoize-one/-/memoize-one-5.2.1.tgz#8337aa3c4335581839ec01c3d594090cebe8f00e"
   integrity sha512-zYiwtZUcYyXKo/np96AGZAckk+FWWsUdJ3cHGGmld7+AhvcWmQyGCYUh1hc4Q/pkOhb65dQR/pqCyK0cOaHz4Q==
@@ -10185,6 +10185,14 @@ react-transition-group@^4.4.5:
     loose-envify "^1.4.0"
     prop-types "^15.6.2"
 
+react-window@^1.8.10:
+  version "1.8.11"
+  resolved "https://registry.yarnpkg.com/react-window/-/react-window-1.8.11.tgz#a857b48fa85bd77042d59cc460964ff2e0648525"
+  integrity sha512-+SRbUVT2scadgFSWx+R1P754xHPEqvcfSfVX10QYg6POOz+WNgkN48pS+BtZNIMGiL1HYrSEiCkwsMS15QogEQ==
+  dependencies:
+    "@babel/runtime" "^7.0.0"
+    memoize-one ">=3.1.1 <6"
+
 react@^16.1.0, react@^16.13.1:
   version "16.14.0"
   resolved "https://registry.yarnpkg.com/react/-/react-16.14.0.tgz#94d776ddd0aaa37da3eda8fc5b6b18a4c9a3114d"