diff --git a/app/models/registrant_user.rb b/app/models/registrant_user.rb
index c0addb5cd..40f48f69c 100644
--- a/app/models/registrant_user.rb
+++ b/app/models/registrant_user.rb
@@ -2,6 +2,7 @@ class RegistrantUser < User
   attr_accessor :idc_data
 
   devise :trackable, :timeoutable
+  after_save :update_related_contacts
 
   def ability
     @ability ||= Ability.new(self)
@@ -54,6 +55,12 @@ class RegistrantUser < User
     username.split.second
   end
 
+  def update_related_contacts
+    cc, idcode = registrant_ident.split('-')
+    contacts = Contact.where(ident: idcode, country_code: cc).where('name != ?', username)
+    contacts.each { |c| c.update(name: username) }
+  end
+
   class << self
     def find_or_create_by_api_data(user_data = {})
       return false unless user_data[:ident]