diff --git a/packages/eslint-plugin/src/rules/prefer-interface.ts b/packages/eslint-plugin/src/rules/prefer-interface.ts
index 5a3d41329a4c..9b601fc00669 100644
--- a/packages/eslint-plugin/src/rules/prefer-interface.ts
+++ b/packages/eslint-plugin/src/rules/prefer-interface.ts
@@ -19,7 +19,7 @@ export default util.createRule({
     },
     schema: [],
     deprecated: true,
-    replacedBy: 'consistent-type-definisions',
+    replacedBy: ['consistent-type-definisions'],
   },
   defaultOptions: [],
   create(context) {
diff --git a/packages/eslint-plugin/typings/ts-eslint.d.ts b/packages/eslint-plugin/typings/ts-eslint.d.ts
index 83c58d548a61..a197e50c2a12 100644
--- a/packages/eslint-plugin/typings/ts-eslint.d.ts
+++ b/packages/eslint-plugin/typings/ts-eslint.d.ts
@@ -262,7 +262,7 @@ declare module 'ts-eslint' {
     /**
      * The name of the rule this rule was replaced by, if it was deprecated.
      */
-    replacedBy?: string;
+    replacedBy?: string[];
     /**
      * The options schema. Supply an empty array if there are no options.
      */