diff --git a/.changeset/tall-eggs-remain.md b/.changeset/tall-eggs-remain.md
new file mode 100644
index 000000000..3b746b932
--- /dev/null
+++ b/.changeset/tall-eggs-remain.md
@@ -0,0 +1,5 @@
+---
+'@farfetched/core': patch
+---
+
+Add missed header Accept in `createJsonQuery`/`createJsonMutation`
diff --git a/packages/core/src/fetch/__tests__/json.request.headers.test.ts b/packages/core/src/fetch/__tests__/json.request.headers.test.ts
index 14fca1fc5..54fd60e29 100644
--- a/packages/core/src/fetch/__tests__/json.request.headers.test.ts
+++ b/packages/core/src/fetch/__tests__/json.request.headers.test.ts
@@ -27,6 +27,7 @@ describe('fetch/json.request.headers', () => {
 
     expect(fetchMock.mock.calls[0][0].headers).toEqual(
       new Headers({
+        Accept: 'application/json',
         'content-type': 'application/json',
       })
     );
@@ -46,6 +47,8 @@ describe('fetch/json.request.headers', () => {
       params: {},
     });
 
-    expect(fetchMock.mock.calls[0][0].headers).toEqual(new Headers({}));
+    expect(fetchMock.mock.calls[0][0].headers).toEqual(
+      new Headers({ Accept: 'application/json' })
+    );
   });
 });
diff --git a/packages/core/src/fetch/json.ts b/packages/core/src/fetch/json.ts
index 20b103e7c..51641ccf9 100644
--- a/packages/core/src/fetch/json.ts
+++ b/packages/core/src/fetch/json.ts
@@ -40,11 +40,16 @@ export function createJsonApiRequest<R extends CreationRequestConfig>(
       headers: normalizeStaticOrReactive(config.request.headers),
     },
     ({ method, headers }) =>
-      ['GET', 'HEAD'].includes(method!) // TODO: fix type inferences
-        ? headers
-        : mergeRecords(headers, {
-            'Content-Type': 'application/json',
-          })
+      // reversed merge order to allow any modifications in the user code
+      mergeRecords(
+        {
+          Accept: 'application/json',
+          'Content-Type': ['GET', 'HEAD'].includes(method)
+            ? undefined
+            : 'application/json',
+        },
+        headers
+      )
   );
 
   const jsonApiCallFx = createApiRequest<