diff --git a/app/assets/javascripts/discourse/app/templates/components/edit-category-settings.hbs b/app/assets/javascripts/discourse/app/templates/components/edit-category-settings.hbs
index 5df8c8dba4d..a4cfaff3647 100644
--- a/app/assets/javascripts/discourse/app/templates/components/edit-category-settings.hbs
+++ b/app/assets/javascripts/discourse/app/templates/components/edit-category-settings.hbs
@@ -233,6 +233,10 @@
         {{i18n "category.email_in"}}
       </label>
       <TextField @id="category-email-in" @class="email-in" @value={{this.category.email_in}} />
+      <span>
+        {{d-icon "info-circle"}}
+        <DTooltip>{{i18n "category.email_in_tooltip"}}</DTooltip>
+      </span>
     </section>
 
     <section class="field email-in-allow-strangers">
diff --git a/config/locales/client.en.yml b/config/locales/client.en.yml
index 8054f4086ff..4f25893a41f 100644
--- a/config/locales/client.en.yml
+++ b/config/locales/client.en.yml
@@ -3534,6 +3534,7 @@ en:
       pending_permission_change_alert: "You haven't added %{group} to this category; click this button to add them."
       images: "Images"
       email_in: "Custom incoming email address:"
+      email_in_tooltip: "You can separate multiple email addresses with the | character."
       email_in_allow_strangers: "Accept emails from anonymous users with no accounts"
       email_in_disabled: "Posting new topics via email is disabled in the Site Settings. To enable posting new topics via email, "
       email_in_disabled_click: 'enable the "email in" setting.'