diff --git a/CHANGELOG.md b/CHANGELOG.md
index eef662602..1301323ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+- Added `isBranchFilteringEnabled` flag to `search_finished` PostHog event. [#781](https://github.com/sourcebot-dev/sourcebot/pull/781)
+
 ## [4.10.15] - 2026-01-22
 
 ### Fixed
diff --git a/packages/web/src/app/[domain]/search/components/searchResultsPage.tsx b/packages/web/src/app/[domain]/search/components/searchResultsPage.tsx
index 8708dc3be..c709fadda 100644
--- a/packages/web/src/app/[domain]/search/components/searchResultsPage.tsx
+++ b/packages/web/src/app/[domain]/search/components/searchResultsPage.tsx
@@ -102,6 +102,13 @@ export const SearchResultsPage = ({
         ])
     }, [searchQuery, setSearchHistory]);
 
+    // Look for any files that are not on the default branch.
+    const isBranchFilteringEnabled = useMemo(() => {
+        return files.some((file) => {
+            return file.branches?.some((branch) => branch !== 'HEAD') ?? false;
+        });
+    }, [files]);
+
     useEffect(() => {
         if (isStreaming || !stats) {
             return;
@@ -138,6 +145,7 @@ export const SearchResultsPage = ({
             flushReason: stats.flushReason,
             fileLanguages,
             isSearchExhaustive: isExhaustive,
+            isBranchFilteringEnabled,
         });
     }, [
         captureEvent,
@@ -147,6 +155,7 @@ export const SearchResultsPage = ({
         stats,
         timeToSearchCompletionMs,
         timeToFirstSearchResultMs,
+        isBranchFilteringEnabled,
     ]);
 
     const onLoadMoreResults = useCallback(() => {
@@ -157,13 +166,7 @@ export const SearchResultsPage = ({
         router.push(url);
     }, [maxMatchCount, router, searchQuery, domain]);
 
-    // Look for any files that are not on the default branch.
-    const isBranchFilteringEnabled = useMemo(() => {
-        return files.some((file) => {
-            return file.branches?.some((branch) => branch !== 'HEAD') ?? false;
-        });
-    }, [files]);
-
+    
     return (
         <div className="flex flex-col h-screen overflow-clip">
             {/* TopBar */}
diff --git a/packages/web/src/lib/posthogEvents.ts b/packages/web/src/lib/posthogEvents.ts
index eee32bc05..ea64f88ee 100644
--- a/packages/web/src/lib/posthogEvents.ts
+++ b/packages/web/src/lib/posthogEvents.ts
@@ -27,7 +27,8 @@ export type PosthogEventMap = {
         regexpsConsidered: number,
         flushReason: string,
         fileLanguages: string[],
-        isSearchExhaustive: boolean
+        isSearchExhaustive: boolean,
+        isBranchFilteringEnabled: boolean,
     },
     ////////////////////////////////////////////////////////////////
     wa_trial_nav_pressed: {},