diff --git a/extensions/vscode/src/extension/services/__tests__/gitMap.test.ts b/extensions/vscode/src/extension/services/__tests__/gitMap.test.ts
index b8eb991a..20a873a4 100644
--- a/extensions/vscode/src/extension/services/__tests__/gitMap.test.ts
+++ b/extensions/vscode/src/extension/services/__tests__/gitMap.test.ts
@@ -205,6 +205,21 @@ describe('pickRepoRoot', () => {
     const roots = ['/a/repo', '/b/repo'];
     expect(pickRepoRoot(roots, undefined)).toBe('/a/repo');
   });
+
+  it('selects a Windows repository containing the workspace subdirectory', () => {
+    const roots = ['C:\\other', 'C:\\repo'];
+    expect(pickRepoRoot(roots, 'C:\\repo\\packages\\app')).toBe('C:\\repo');
+  });
+
+  it('does not treat a Windows path with the same prefix as an ancestor', () => {
+    const roots = ['C:\\repo', 'C:\\repository'];
+    expect(pickRepoRoot(roots, 'C:\\repository\\src')).toBe('C:\\repository');
+  });
+
+  it('handles mixed separators between a UNC root and workspace path', () => {
+    const roots = ['//server/share/other', '//server/share/repo'];
+    expect(pickRepoRoot(roots, '\\\\server\\share\\repo\\src')).toBe('//server/share/repo');
+  });
 });
 
 describe('getCommitFiles: git show revision placement', () => {
diff --git a/extensions/vscode/src/extension/services/gitMap.ts b/extensions/vscode/src/extension/services/gitMap.ts
index 68b3e21b..6fbc2932 100644
--- a/extensions/vscode/src/extension/services/gitMap.ts
+++ b/extensions/vscode/src/extension/services/gitMap.ts
@@ -1,4 +1,5 @@
 import { FileChange } from '../../shared/types';
+import path from 'path';
 
 export function mapStatusCode(code: string): FileChange['status'] {
   switch (code) {
@@ -87,12 +88,20 @@ export function pickRepoRoot(roots: string[], workspacePath?: string): string |
   if (roots.length === 0) return null;
   if (!workspacePath) return roots[0];
 
-  const exact = roots.find((r) => r === workspacePath);
-  if (exact) return exact;
+  const candidates = roots.map((root) => {
+    const isWindowsPath = [root, workspacePath].some((p) => /^[a-z]:[\\/]/i.test(p) || p.includes('\\'));
+    const pathApi = isWindowsPath ? path.win32 : path.posix;
+    return { root, relative: pathApi.relative(root, workspacePath), pathApi };
+  });
 
-  const ancestors = roots.filter((r) => workspacePath.startsWith(r.endsWith('/') ? r : r + '/'));
+  const exact = candidates.find(({ relative }) => relative === '');
+  if (exact) return exact.root;
+
+  const ancestors = candidates.filter(({ relative, pathApi }) =>
+    relative !== '..' && !relative.startsWith(`..${pathApi.sep}`) && !pathApi.isAbsolute(relative));
   if (ancestors.length > 0) {
-    return ancestors.reduce((deepest, r) => (r.length > deepest.length ? r : deepest));
+    return ancestors.reduce((deepest, candidate) =>
+      candidate.relative.length < deepest.relative.length ? candidate : deepest).root;
   }
 
   return roots[0];