diff --git a/packages/ra-core/src/controller/saveContext/SaveContext.ts b/packages/ra-core/src/controller/saveContext/SaveContext.ts
index 8b9797de353..c33221ba9a6 100644
--- a/packages/ra-core/src/controller/saveContext/SaveContext.ts
+++ b/packages/ra-core/src/controller/saveContext/SaveContext.ts
@@ -1,7 +1,7 @@
 import { createContext } from 'react';
 import {
     RaRecord,
-    onError,
+    OnError,
     OnSuccess,
     TransformData,
     MutationMode,
@@ -23,7 +23,7 @@ export type SaveHandler<RecordType> = (
     record: Partial<RecordType>,
     callbacks?: {
         onSuccess?: OnSuccess;
-        onError?: onError;
+        onError?: OnError;
         transform?: TransformData;
     }
 ) => Promise<void | RecordType> | Record<string, string>;
diff --git a/packages/ra-core/src/types.ts b/packages/ra-core/src/types.ts
index be2bcbe9dae..3b210fee4d6 100644
--- a/packages/ra-core/src/types.ts
+++ b/packages/ra-core/src/types.ts
@@ -247,7 +247,11 @@ export type OnSuccess = (
     variables?: any,
     context?: any
 ) => void;
-export type onError = (error?: any, variables?: any, context?: any) => void;
+
+// @deprecated - use OnError instead
+export type OnError = (error?: any, variables?: any, context?: any) => void;
+export type onError = OnError;
+
 export type TransformData = (
     data: any,
     options?: { previousData: any }