diff --git a/src/amo/components/Addon/index.js b/src/amo/components/Addon/index.js
index 300f27dd49e..7b7295543e8 100644
--- a/src/amo/components/Addon/index.js
+++ b/src/amo/components/Addon/index.js
@@ -226,7 +226,7 @@ export class AddonBase extends React.Component {
 
     return (
       <ShowMoreCard
-        header={i18n.sprintf(i18n.gettext('About this %(addonType)s'), { addonType })}
+        header={i18n.sprintf(i18n.gettext('About this %(addonType)s'), { addonType: i18n.addonType(addonType) })}
         className="AddonDescription"
       >
         <div
diff --git a/src/amo/components/RatingManager/index.js b/src/amo/components/RatingManager/index.js
index 798e632ad8a..f0cd31870f0 100644
--- a/src/amo/components/RatingManager/index.js
+++ b/src/amo/components/RatingManager/index.js
@@ -11,14 +11,6 @@ import { setReview } from 'amo/actions/reviews';
 import { getLatestUserReview, submitReview } from 'amo/api';
 import DefaultAddonReview from 'amo/components/AddonReview';
 import DefaultAuthenticateButton from 'core/components/AuthenticateButton';
-import {
-  ADDON_TYPE_DICT,
-  ADDON_TYPE_EXTENSION,
-  ADDON_TYPE_LANG,
-  ADDON_TYPE_OPENSEARCH,
-  ADDON_TYPE_THEME,
-  validAddonTypes as defaultValidAddonTypes,
-} from 'core/constants';
 import translate from 'core/i18n/translate';
 import log from 'core/logger';
 import DefaultRating from 'ui/components/Rating';
@@ -111,33 +103,13 @@ export class RatingManagerBase extends React.Component {
       });
   }
 
-  getLogInPrompt(
-    { addonType }: {| addonType: string |},
-    {
-      validAddonTypes = defaultValidAddonTypes,
-      }: {|
-      validAddonTypes: typeof defaultValidAddonTypes,
-    |} = {}
-  ) {
+  getLogInPrompt({ addonType }: {| addonType: string |}) {
     const { i18n } = this.props;
-    switch (addonType) {
-      case ADDON_TYPE_DICT:
-        return i18n.gettext('Log in to rate this dictionary');
-      case ADDON_TYPE_LANG:
-        return i18n.gettext('Log in to rate this language pack');
-      case ADDON_TYPE_OPENSEARCH:
-        return i18n.gettext('Log in to rate this search plugin');
-      case ADDON_TYPE_THEME:
-        return i18n.gettext('Log in to rate this theme');
-      case ADDON_TYPE_EXTENSION:
-        return i18n.gettext('Log in to rate this extension');
-      default:
-        if (!validAddonTypes.includes(addonType)) {
-          throw new Error(`Unknown extension type: ${addonType}`);
-        }
-        log.warn(`Using generic prompt for add-on type: ${addonType}`);
-        return i18n.gettext('Log in to rate this add-on');
-    }
+
+    return i18n.sprintf(
+      i18n.gettext('Log in to rate this %(addonType)s'),
+      { addonType: i18n.addonType(addonType) }
+    );
   }
 
   renderLogInToRate() {
diff --git a/src/core/i18n/utils.js b/src/core/i18n/utils.js
index 7260b3e1090..b4d9d22f28c 100644
--- a/src/core/i18n/utils.js
+++ b/src/core/i18n/utils.js
@@ -5,6 +5,15 @@ import Jed from 'jed';
 import moment from 'moment';
 
 import log from 'core/logger';
+import {
+  ADDON_TYPE_COMPLETE_THEME,
+  ADDON_TYPE_DICT,
+  ADDON_TYPE_EXTENSION,
+  ADDON_TYPE_LANG,
+  ADDON_TYPE_OPENSEARCH,
+  ADDON_TYPE_THEME,
+  validAddonTypes,
+} from 'core/constants';
 
 const defaultLang = config.get('defaultLang');
 const langs = config.get('langs');
@@ -287,6 +296,30 @@ export function makeI18n(
       oneLineTranslationString(pluralKey), val);
   };
 
+  // The `addonType` we use internally is not translated, so we use this helper
+  // to return translated add-on type names.
+  i18n.addonType = function addonType(type) {
+    switch (type) {
+      case ADDON_TYPE_DICT:
+        return i18n.gettext('dictionary');
+      case ADDON_TYPE_LANG:
+        return i18n.gettext('language pack');
+      case ADDON_TYPE_OPENSEARCH:
+        return i18n.gettext('search plugin');
+      case ADDON_TYPE_THEME:
+      case ADDON_TYPE_COMPLETE_THEME:
+        return i18n.gettext('theme');
+      case ADDON_TYPE_EXTENSION:
+        return i18n.gettext('extension');
+      default:
+        if (!validAddonTypes.includes(type)) {
+          throw new Error(`Unknown extension type: ${type}`);
+        }
+        log.warn(`Using generic prompt for add-on type: ${type}`);
+        return i18n.gettext('add-on');
+    }
+  };
+
   // We add a translated "moment" property to our `i18n` object
   // to make translated date/time/etc. easy.
   i18n.moment = moment;
diff --git a/tests/unit/core/i18n/test_utils.js b/tests/unit/core/i18n/test_utils.js
index 52c51e83c49..a44fb7f3fdc 100644
--- a/tests/unit/core/i18n/test_utils.js
+++ b/tests/unit/core/i18n/test_utils.js
@@ -3,6 +3,14 @@ import moment from 'moment';
 import { oneLine } from 'common-tags';
 
 import * as utils from 'core/i18n/utils';
+import {
+  ADDON_TYPE_COMPLETE_THEME,
+  ADDON_TYPE_DICT,
+  ADDON_TYPE_EXTENSION,
+  ADDON_TYPE_LANG,
+  ADDON_TYPE_OPENSEARCH,
+  ADDON_TYPE_THEME,
+} from 'core/constants';
 
 
 const defaultLang = config.get('defaultLang');
@@ -394,7 +402,10 @@ describe('i18n utils', () => {
   describe('makeI18n', () => {
     class FakeJed {
       constructor(i18nData) {
-        return i18nData;
+        return {
+          ...i18nData,
+          gettext: (key) => key,
+        };
       }
     }
 
@@ -475,5 +486,24 @@ describe('i18n utils', () => {
       sinon.assert.calledWith(toLocaleStringSpy, 'fr');
       sinon.assert.notCalled(numberFormatSpy);
     });
+
+    describe('addonType()', () => {
+      it('translates internal addon types', () => {
+        const i18n = utils.makeI18n({}, 'en', FakeJed);
+        expect(i18n.addonType(ADDON_TYPE_COMPLETE_THEME)).toEqual('theme');
+        expect(i18n.addonType(ADDON_TYPE_DICT)).toEqual('dictionary');
+        expect(i18n.addonType(ADDON_TYPE_EXTENSION)).toEqual('extension');
+        expect(i18n.addonType(ADDON_TYPE_LANG)).toEqual('language pack');
+        expect(i18n.addonType(ADDON_TYPE_OPENSEARCH)).toEqual('search plugin');
+        expect(i18n.addonType(ADDON_TYPE_THEME)).toEqual('theme');
+      });
+
+      it('throws an error if the given type is not valid', () => {
+        const i18n = utils.makeI18n({}, 'en', FakeJed);
+        expect(() => {
+          i18n.addonType('unknown-type');
+        }).toThrowError(/Unknown extension type/);
+      });
+    });
   });
 });