diff --git a/supervisor/api/backups.py b/supervisor/api/backups.py
index 169819f3364..0e50b687de1 100644
--- a/supervisor/api/backups.py
+++ b/supervisor/api/backups.py
@@ -46,7 +46,7 @@
     CoreState,
 )
 from ..coresys import CoreSysAttributes
-from ..exceptions import APIError, APIForbidden
+from ..exceptions import APIError, APIForbidden, APINotFound
 from ..jobs import JobSchedulerOptions
 from ..mounts.const import MountUsage
 from ..resolution.const import UnhealthyReason
@@ -134,7 +134,7 @@ def _extract_slug(self, request):
         """Return backup, throw an exception if it doesn't exist."""
         backup = self.sys_backups.get(request.match_info.get("slug"))
         if not backup:
-            raise APIError("Backup does not exist")
+            raise APINotFound("Backup does not exist")
         return backup
 
     def _list_backups(self):
diff --git a/supervisor/exceptions.py b/supervisor/exceptions.py
index 0120b1d1f47..550bf26d0e5 100644
--- a/supervisor/exceptions.py
+++ b/supervisor/exceptions.py
@@ -336,6 +336,12 @@ class APIForbidden(APIError):
     status = 403
 
 
+class APINotFound(APIError):
+    """API not found error."""
+
+    status = 404
+
+
 class APIAddonNotInstalled(APIError):
     """Not installed addon requested at addons API."""
 
diff --git a/tests/api/test_backups.py b/tests/api/test_backups.py
index 53eacd2b10e..757a41d2e00 100644
--- a/tests/api/test_backups.py
+++ b/tests/api/test_backups.py
@@ -729,3 +729,21 @@ async def test_upload_duplicate_backup_new_location(
         ".cloud_backup": copy_backup,
     }
     assert coresys.backups.get("7fed74c8").location is None
+
+
+@pytest.mark.parametrize(
+    ("method", "url"),
+    [
+        ("get", "/backups/bad/info"),
+        ("delete", "/backups/bad"),
+        ("post", "/backups/bad/restore/full"),
+        ("post", "/backups/bad/restore/partial"),
+        ("get", "/backups/bad/download"),
+    ],
+)
+async def test_backup_not_found(api_client: TestClient, method: str, url: str):
+    """Test backup not found error."""
+    resp = await api_client.request(method, url)
+    assert resp.status == 404
+    resp = await resp.json()
+    assert resp["message"] == "Backup does not exist"