diff --git a/packages/nodes-base/credentials/MailchimpOAuth2Api.credentials.ts b/packages/nodes-base/credentials/MailchimpOAuth2Api.credentials.ts
index 857229c728..f4adbd0b09 100644
--- a/packages/nodes-base/credentials/MailchimpOAuth2Api.credentials.ts
+++ b/packages/nodes-base/credentials/MailchimpOAuth2Api.credentials.ts
@@ -49,7 +49,7 @@ export class MailchimpOAuth2Api implements ICredentialType {
 			displayName: 'Authentication',
 			name: 'authentication',
 			type: 'hidden' as NodePropertyTypes,
-			default: 'header',
+			default: 'body',
 		},
 	];
 }