diff --git a/packages/angular-db/tests/inject-live-query.test-d.ts b/packages/angular-db/tests/inject-live-query.test-d.ts
new file mode 100644
index 000000000..667e11314
--- /dev/null
+++ b/packages/angular-db/tests/inject-live-query.test-d.ts
@@ -0,0 +1,138 @@
+import { describe, expectTypeOf, it } from 'vitest'
+import { createCollection } from '../../db/src/collection/index'
+import { mockSyncCollectionOptions } from '../../db/tests/utils'
+import {
+  createLiveQueryCollection,
+  eq,
+  liveQueryCollectionOptions,
+} from '../../db/src/query/index'
+import { injectLiveQuery } from '../src/index'
+import type { SingleResult } from '../../db/src/types'
+
+type Person = {
+  id: string
+  name: string
+  age: number
+  email: string
+  isActive: boolean
+  team: string
+}
+
+describe(`injectLiveQuery type assertions`, () => {
+  it(`should type findOne query builder to return a single row`, () => {
+    const collection = createCollection(
+      mockSyncCollectionOptions<Person>({
+        id: `test-persons-findone-angular`,
+        getKey: (person: Person) => person.id,
+        initialData: [],
+      }),
+    )
+
+    const { data } = injectLiveQuery((q) =>
+      q
+        .from({ collection })
+        .where(({ collection: c }) => eq(c.id, `3`))
+        .findOne(),
+    )
+
+    // findOne returns a single result or undefined
+    expectTypeOf(data()).toEqualTypeOf<Person | undefined>()
+  })
+
+  it(`should type findOne config object to return a single row`, () => {
+    const collection = createCollection(
+      mockSyncCollectionOptions<Person>({
+        id: `test-persons-findone-config-angular`,
+        getKey: (person: Person) => person.id,
+        initialData: [],
+      }),
+    )
+
+    const { data } = injectLiveQuery({
+      params: () => ({ id: `3` }),
+      query: ({ params, q }) =>
+        q
+          .from({ collection })
+          .where(({ collection: c }) => eq(c.id, params.id))
+          .findOne(),
+    })
+
+    // findOne returns a single result or undefined
+    expectTypeOf(data()).toEqualTypeOf<Person | undefined>()
+  })
+
+  it(`should type findOne collection using liveQueryCollectionOptions to return a single row`, () => {
+    const collection = createCollection(
+      mockSyncCollectionOptions<Person>({
+        id: `test-persons-findone-options-angular`,
+        getKey: (person: Person) => person.id,
+        initialData: [],
+      }),
+    )
+
+    const options = liveQueryCollectionOptions({
+      query: (q) =>
+        q
+          .from({ collection })
+          .where(({ collection: c }) => eq(c.id, `3`))
+          .findOne(),
+    })
+
+    const liveQueryCollection = createCollection(options)
+
+    expectTypeOf(liveQueryCollection).toExtend<SingleResult>()
+
+    const { data } = injectLiveQuery(liveQueryCollection)
+
+    // findOne returns a single result or undefined
+    expectTypeOf(data()).toEqualTypeOf<Person | undefined>()
+  })
+
+  it(`should type findOne collection using createLiveQueryCollection to return a single row`, () => {
+    const collection = createCollection(
+      mockSyncCollectionOptions<Person>({
+        id: `test-persons-findone-create-angular`,
+        getKey: (person: Person) => person.id,
+        initialData: [],
+      }),
+    )
+
+    const liveQueryCollection = createLiveQueryCollection({
+      query: (q) =>
+        q
+          .from({ collection })
+          .where(({ collection: c }) => eq(c.id, `3`))
+          .findOne(),
+    })
+
+    expectTypeOf(liveQueryCollection).toExtend<SingleResult>()
+
+    const { data } = injectLiveQuery(liveQueryCollection)
+
+    // findOne returns a single result or undefined
+    expectTypeOf(data()).toEqualTypeOf<Person | undefined>()
+  })
+
+  it(`should type regular query to return an array`, () => {
+    const collection = createCollection(
+      mockSyncCollectionOptions<Person>({
+        id: `test-persons-array-angular`,
+        getKey: (person: Person) => person.id,
+        initialData: [],
+      }),
+    )
+
+    const { data } = injectLiveQuery((q) =>
+      q
+        .from({ collection })
+        .where(({ collection: c }) => eq(c.isActive, true))
+        .select(({ collection: c }) => ({
+          id: c.id,
+          name: c.name,
+        })),
+    )
+
+    // Regular queries should return an array
+    expectTypeOf(data()).toEqualTypeOf<Array<{ id: string; name: string }>>()
+  })
+})
diff --git a/packages/angular-db/tests/inject-live-query.test.ts b/packages/angular-db/tests/inject-live-query.test.ts
index 2f4db01ca..81fbb12a9 100644
--- a/packages/angular-db/tests/inject-live-query.test.ts
+++ b/packages/angular-db/tests/inject-live-query.test.ts
@@ -14,6 +14,7 @@ import type {
   CollectionStatus,
   Context,
   LiveQueryCollectionConfig,
+  NonSingleResult,
   QueryBuilder,
 } from '@tanstack/db'
 
@@ -66,12 +67,13 @@ async function waitForAngularUpdate() {
 function createMockCollection<T extends object, K extends string | number>(
   initial: Array<T & Record<`id`, K>> = [],
   initialStatus: CollectionStatus = `ready`,
-): Collection<T, K, Record<string, never>> & {
-  __setStatus: (s: CollectionStatus) => void
-  __replaceAll: (rows: Array<T & Record<`id`, K>>) => void
-  __upsert: (row: T & Record<`id`, K>) => void
-  __delete: (key: K) => void
-} {
+): Collection<T, K, Record<string, never>> &
+  NonSingleResult & {
+    __setStatus: (s: CollectionStatus) => void
+    __replaceAll: (rows: Array<T & Record<`id`, K>>) => void
+    __upsert: (row: T & Record<`id`, K>) => void
+    __delete: (key: K) => void
+  } {
   const map = new Map<K, T>()
   for (const r of initial) {
     map.set(r.id, r)
@@ -532,7 +534,7 @@ describe(`injectLiveQuery`, () => {
 
       await waitForAngularUpdate()
 
-      expect(res.collection().id).toEqual(expect.any(String))
+      expect(res.collection()!.id).toEqual(expect.any(String))
       expect(res.status()).toBe(`ready`)
       expect(Array.isArray(res.data())).toBe(true)
       expect(res.state() instanceof Map).toBe(true)
@@ -565,7 +567,7 @@ describe(`injectLiveQuery`, () => {
       const res = injectLiveQuery(config)
       await waitForAngularUpdate()
 
-      expect(res.collection().id).toEqual(expect.any(String))
+      expect(res.collection()!.id).toEqual(expect.any(String))
       expect(res.isReady()).toBe(true)
     })
   })
@@ -611,7 +613,7 @@ describe(`injectLiveQuery`, () => {
 
       await waitForAngularUpdate()
 
-      expect(res.collection().id).toEqual(expect.any(String))
+      expect(res.collection()!.id).toEqual(expect.any(String))
       expect(res.status()).toBe(`ready`)
       expect(Array.isArray(res.data())).toBe(true)
       expect(res.state() instanceof Map).toBe(true)
@@ -752,6 +754,40 @@ describe(`injectLiveQuery`, () => {
     })
   })
 
+  it(`should return a single object for findOne query`, async () => {
+    await TestBed.runInInjectionContext(async () => {
+      const collection = createCollection(
+        mockSyncCollectionOptions<Person>({
+          id: `test-persons-findone-angular`,
+          getKey: (person: Person) => person.id,
+          initialData: initialPersons,
+        }),
+      )
+
+      const { state, data } = injectLiveQuery((q) =>
+        q
+          .from({ collection })
+          .where(({ collection: c }) => eq(c.id, `3`))
+          .findOne(),
+      )
+
+      await waitForAngularUpdate()
+
+      expect(state().size).toBe(1)
+      expect(state().get(`3`)).toMatchObject({
+        id: `3`,
+        name: `John Smith`,
+      })
+
+      // findOne should return a single object, not an array
+      expect(Array.isArray(data())).toBe(false)
+      expect(data()).toMatchObject({
+        id: `3`,
+        name: `John Smith`,
+      })
+    })
+  })
+
   describe(`eager execution during sync`, () => {
     it(`should show state while isLoading is true during sync`, async () => {
       await TestBed.runInInjectionContext(async () => {
@@ -795,7 +831,7 @@ describe(`injectLiveQuery`, () => {
         })
 
         // Start the live query sync manually
-        liveQueryCollection().preload()
+        liveQueryCollection()!.preload()
 
         await waitForAngularUpdate()
 
@@ -907,7 +943,7 @@ describe(`injectLiveQuery`, () => {
         })
 
         // Start the live query sync manually
-        liveQueryCollection().preload()
+        liveQueryCollection()!.preload()
 
         await waitForAngularUpdate()
 
@@ -1007,7 +1043,7 @@ describe(`injectLiveQuery`, () => {
         })
 
         // Start the live query sync manually
-        liveQueryCollection().preload()
+        liveQueryCollection()!.preload()
 
         await waitForAngularUpdate()