diff --git a/app/assets/javascripts/discourse/components/csv-uploader.js.es6 b/app/assets/javascripts/discourse/components/csv-uploader.js.es6
index d89aaae30b7..70637588687 100644
--- a/app/assets/javascripts/discourse/components/csv-uploader.js.es6
+++ b/app/assets/javascripts/discourse/components/csv-uploader.js.es6
@@ -6,6 +6,10 @@ export default Em.Component.extend(UploadMixin, {
   tagName: "span",
   uploadUrl: "/invites/upload_csv",
 
+  validateUploadedFilesOptions() {
+    return { csvOnly: true };
+  },
+
   @computed("uploading")
   uploadButtonText(uploading) {
     return uploading ? I18n.t("uploading") : I18n.t("user.invited.bulk_invite.text");
diff --git a/app/assets/javascripts/discourse/lib/utilities.js.es6 b/app/assets/javascripts/discourse/lib/utilities.js.es6
index 154f92553b5..5eeb3a358c4 100644
--- a/app/assets/javascripts/discourse/lib/utilities.js.es6
+++ b/app/assets/javascripts/discourse/lib/utilities.js.es6
@@ -192,6 +192,11 @@ export function validateUploadedFile(file, opts) {
       bootbox.alert(I18n.t('post.errors.upload_not_authorized', { authorized_extensions: authorizedImagesExtensions() }));
       return false;
     }
+  } else if (opts["csvOnly"]) {
+    if (!(/\.csv$/i).test(name)) {
+      bootbox.alert(I18n.t('user.invited.bulk_invite.error'));
+      return false;
+    }
   } else {
     if (!authorizesAllExtensions() && !isAuthorizedFile(name)) {
       bootbox.alert(I18n.t('post.errors.upload_not_authorized', { authorized_extensions: authorizedExtensions() }));
diff --git a/app/controllers/invites_controller.rb b/app/controllers/invites_controller.rb
index ae62b9b8732..5b614bc3dc6 100644
--- a/app/controllers/invites_controller.rb
+++ b/app/controllers/invites_controller.rb
@@ -156,9 +156,9 @@ class InvitesController < ApplicationController
 
     Scheduler::Defer.later("Upload CSV") do
       begin
-        data = if extension == ".csv"
+        data = if extension.downcase == ".csv"
           path = Invite.create_csv(file, name)
-          Jobs.enqueue(:bulk_invite, filename: "#{name}.csv", current_user_id: current_user.id)
+          Jobs.enqueue(:bulk_invite, filename: "#{name}#{extension}", current_user_id: current_user.id)
           {url: path}
         else
           failed_json.merge(errors: [I18n.t("bulk_invite.file_should_be_csv")])
diff --git a/config/locales/client.en.yml b/config/locales/client.en.yml
index 14d88913f01..bbe0aab2c83 100644
--- a/config/locales/client.en.yml
+++ b/config/locales/client.en.yml
@@ -833,6 +833,7 @@ en:
           none: "You haven't invited anyone here yet. You can send individual invites, or invite a bunch of people at once by <a href='https://meta.discourse.org/t/send-bulk-invites/16468'>uploading a CSV file</a>."
           text: "Bulk Invite from File"
           success: "File uploaded successfully, you will be notified via message when the process is complete."
+          error: "Sorry, file should be of csv format."
 
       password:
         title: "Password"