diff --git a/src/adapter/chrome.ts b/src/adapter/chrome.ts
index ebfe409..600f636 100644
--- a/src/adapter/chrome.ts
+++ b/src/adapter/chrome.ts
@@ -67,14 +67,16 @@ export const createChromeHandler = <TRouter extends AnyRouter>(
 
         sendResponse({
           // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
-          error: getErrorShape({
-            config: router._def._config,
-            error,
-            type: method,
-            path: params.path,
-            input: params.input,
-            ctx,
-          }),
+          error: transformer.output.serialize(
+            getErrorShape({
+              config: router._def._config,
+              error,
+              type: method,
+              path: params.path,
+              input: params.input,
+              ctx,
+            }),
+          ),
         });
       };
 
diff --git a/src/adapter/window.ts b/src/adapter/window.ts
index 7d7c2c3..b8a82db 100644
--- a/src/adapter/window.ts
+++ b/src/adapter/window.ts
@@ -73,14 +73,16 @@ export const createWindowHandler = <TRouter extends AnyRouter>(
 
       sendResponse({
         // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
-        error: getErrorShape({
-          config: router._def._config,
-          error,
-          type: method,
-          path: params.path,
-          input: params.input,
-          ctx,
-        }),
+        error: transformer.output.serialize(
+          getErrorShape({
+            config: router._def._config,
+            error,
+            type: method,
+            path: params.path,
+            input: params.input,
+            ctx,
+          }),
+        ),
       });
     };