diff --git a/app/jobs/process_submitter_completion_job.rb b/app/jobs/process_submitter_completion_job.rb
index 129b2363..897ff350 100644
--- a/app/jobs/process_submitter_completion_job.rb
+++ b/app/jobs/process_submitter_completion_job.rb
@@ -3,6 +3,9 @@
 class ProcessSubmitterCompletionJob
   include Sidekiq::Job
 
+  BCC_LIMIT = 14
+  TooManyBcc = Class.new(StandardError)
+
   def perform(params = {})
     submitter = Submitter.find(params['submitter_id'])
     submission = submitter.submission
@@ -133,16 +136,24 @@ class ProcessSubmitterCompletionJob
           true
         end
 
-      build_bcc_addresses(submission).each do |to|
-        next if is_sent_to_user && to == user.email
-
-        SubmitterMailer.completed_email(submitter, user, to:).deliver_later!
-      end
+      enqueue_bcc_completed_emails(submitter, user, is_sent_to_user)
     end
 
     maybe_enqueue_copy_emails(submitter)
   end
 
+  def enqueue_bcc_completed_emails(submitter, user, is_sent_to_user)
+    bcc_addresses = build_bcc_addresses(submitter.submission)
+
+    raise TooManyBcc, submitter.account_id if Docuseal.multitenant? && bcc_addresses.size > BCC_LIMIT
+
+    bcc_addresses.each do |to|
+      next if is_sent_to_user && to == user.email
+
+      SubmitterMailer.completed_email(submitter, user, to:).deliver_later!
+    end
+  end
+
   def maybe_enqueue_copy_emails(submitter)
     return if submitter.template&.preferences&.dig('documents_copy_email_enabled') == false