diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5fbf795..94a6a9a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,13 @@
 
 ## Unreleased
 
+### Breaking Changes
+
+- **Config file renamed** (HYBIM-918): The on-disk credentials file written to
+  `~/.galileo/` has been renamed from `galileo-python-config.json` to
+  `splunk-ao-config.json`. Users with an existing saved config must either rename
+  the file manually or delete it and re-authenticate.
+
 ### Added
 
 - Added deployment-aware configuration and authentication for Splunk
diff --git a/splunk-ao-migration-tool/README.md b/splunk-ao-migration-tool/README.md
index c972e23..f900a54 100644
--- a/splunk-ao-migration-tool/README.md
+++ b/splunk-ao-migration-tool/README.md
@@ -340,6 +340,16 @@ The `GalileoScorers` enum has been removed entirely. Migrate to `SplunkAOEvaluat
 + scorer = SplunkAOEvaluators.completeness
 ```
 
+### 5.3 On-Disk Config File Renamed
+
+The SDK credentials file written to `~/.galileo/` has been renamed:
+
+| Old | New |
+|-----|-----|
+| `~/.galileo/galileo-python-config.json` | `~/.galileo/splunk-ao-config.json` |
+
+If you have saved credentials on disk, either rename the file manually or delete it and re-authenticate by running your code once.
+
 ---
 
 ## 6. HTTP Tracing Headers
@@ -422,13 +432,13 @@ The following are **unchanged** between galileo and splunk-ao and require no mig
 - Optional extra names (`[langchain]`, `[openai]`, `[otel]`, `[all]`, etc.)
 - `TracingMiddleware` class name
 - `OPENAI_API_KEY` environment variable
-- On-disk config file name: `galileo-python-config.json`
 - Default console/API URLs (`https://app.galileo.ai/`, `https://api.galileo.ai/`)
 
 ---
 
 ## 9. Migration Checklist
 
+- [ ] Rename on-disk config file: `~/.galileo/galileo-python-config.json` → `~/.galileo/splunk-ao-config.json` (or delete it and re-authenticate)
 - [ ] Update Python to **≥ 3.11**
 - [ ] Replace `galileo` with `splunk-ao` in `requirements.txt` / `pyproject.toml`
 - [ ] Add `grpcio>=1.80.0,<2.0.0` if using the `otel` extra (or use `splunk-ao[otel]`)
diff --git a/src/splunk_ao/config.py b/src/splunk_ao/config.py
index 58cf391..bf00281 100644
--- a/src/splunk_ao/config.py
+++ b/src/splunk_ao/config.py
@@ -71,7 +71,7 @@ class SplunkAOConfig(GalileoConfig):
     """Configure authentication and endpoints for standalone and O11y deployments."""
 
     # Config file for this project.
-    config_filename: str = "galileo-python-config.json"
+    config_filename: str = "splunk-ao-config.json"
     console_url: Url = DEFAULT_CONSOLE_URL
 
     _instance: ClassVar[Optional["SplunkAOConfig"]] = None
diff --git a/tests/test_config.py b/tests/test_config.py
index 34834e1..cbe50db 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -341,3 +341,7 @@ def test_reset_removes_all_bridgeable_galileo_vars() -> None:
                 f"reset() is expected to remove {galileo_key} "
                 f"(bridge owns all GALILEO_* keys; no SDK consumer sets them directly)"
             )
+
+
+def test_config_filename_default() -> None:
+    assert SplunkAOConfig.model_fields["config_filename"].default == "splunk-ao-config.json"