diff --git a/types/i18n-js/i18n-js-tests.ts b/types/i18n-js/i18n-js-tests.ts
index 8a7480d18e..de5ea45ee1 100644
--- a/types/i18n-js/i18n-js-tests.ts
+++ b/types/i18n-js/i18n-js-tests.ts
@@ -18,6 +18,11 @@ I18n.t("some.missing.scope", { defaults: [{ scope: "some.existing.scope" }] });
 I18n.t("some.missing.scope", { defaults: [{ message: "Some message" }] });
 
 I18n.fallbacks = true;
+I18n.fallbacks = "de";
+I18n.fallbacks = {
+    de: "en",
+    "de-DE": [ "de", "en" ]
+};
 I18n.locales.no = ["nb", "en"];
 I18n.locales.no = "nb";
 I18n.locales.no = locale => ["nb"];
diff --git a/types/i18n-js/index.d.ts b/types/i18n-js/index.d.ts
index 887d59effd..0d5987edf6 100644
--- a/types/i18n-js/index.d.ts
+++ b/types/i18n-js/index.d.ts
@@ -15,7 +15,7 @@ declare namespace I18n {
     let locale: string;
     let defaultSeparator: string;
     let placeholder: RegExp;
-    let fallbacks: boolean;
+    let fallbacks: boolean | string | { [locale: string]: string | string[] };
     let missingBehaviour: "message" | "guess";
     let missingTranslationPrefix: string;