diff --git a/packages/feathers/index.d.ts b/packages/feathers/index.d.ts
index 931d86a4ab..869620320b 100644
--- a/packages/feathers/index.d.ts
+++ b/packages/feathers/index.d.ts
@@ -133,7 +133,7 @@ declare namespace createApplication {
         before: Partial<HookMap> | Hook | Hook[];
         after: Partial<HookMap> | Hook | Hook[];
         error: Partial<HookMap> | Hook | Hook[];
-        finally: Partial<HookMap> | Hook | Hook[];
+        finally?: Partial<HookMap> | Hook | Hook[];
     }
 
     // todo: figure out what to do: These methods don't actually need to be