diff --git a/app/models/enterprise.rb b/app/models/enterprise.rb
index b369712fb1..823c161e3d 100644
--- a/app/models/enterprise.rb
+++ b/app/models/enterprise.rb
@@ -133,6 +133,9 @@ class Enterprise < ApplicationRecord
               message: Spree.t('errors.messages.invalid_instagram_url')
             }, allow_blank: true
   validate :validate_white_label_logo_link
+  validates :external_billing_id,
+            format: { with: /\A\S+\Z/ },
+            allow_blank: true
 
   before_validation :initialize_permalink, if: lambda { permalink.nil? }
   before_validation :set_unused_address_fields