diff --git a/Gemfile b/Gemfile
index 050c95ba0..0804ca4db 100644
--- a/Gemfile
+++ b/Gemfile
@@ -18,7 +18,6 @@ gem 'ransack', '~> 2.3'
 gem 'truemail', '~> 1.7' # validates email by regexp, mail server existence and address existence
 gem 'validates_email_format_of', '1.6.3' # validates email against RFC 2822 and RFC 3696
 
-
 # 0.7.3 is the latest for Rails 4.2, however, it is absent on Rubygems server
 # https://github.com/huacnlee/rails-settings-cached/issues/165
 gem 'rails-settings-cached', '0.7.2'
diff --git a/app/models/registrar.rb b/app/models/registrar.rb
index dbdd7e8d3..2e2051542 100644
--- a/app/models/registrar.rb
+++ b/app/models/registrar.rb
@@ -29,14 +29,11 @@ class Registrar < ApplicationRecord
   validates :vat_rate, numericality: { greater_than_or_equal_to: 0, less_than: 100 },
             allow_nil: true
 
-  validate :forbid_special_code
-
   attribute :vat_rate, ::Type::VATRate.new
   after_initialize :set_defaults
 
-  validates :email, email_format: { message: :invalid },
-            allow_blank: true, if: proc { |c| c.will_save_change_to_email? }
-  validates :billing_email, email_format: { message: :invalid }, allow_blank: true
+  validate :correct_email_format, if: proc { |c| c.will_save_change_to_email? }
+  validate :correct_billing_email_format
 
   alias_attribute :contact_email, :email
 
@@ -196,4 +193,18 @@ class Registrar < ApplicationRecord
   def vat_liable_in_foreign_country?
     !vat_liable_locally?
   end
+
+  def verify_email_mx_smtp(field:, email:)
+    errors.add(field, :invalid) unless email.blank? || Truemail.valid?(email)
+  end
+
+  def correct_email_format
+    verify_email_mx_smtp(field: :email, email: email)
+  end
+
+  def correct_billing_email_format
+    return if self[:billing_email].blank?
+
+    verify_email_mx_smtp(field: :billing_email, email: billing_email)
+  end
 end
diff --git a/config/initializers/truemail.rb b/config/initializers/truemail.rb
index efcecd508..337ac8605 100644
--- a/config/initializers/truemail.rb
+++ b/config/initializers/truemail.rb
@@ -28,7 +28,11 @@ Truemail.configure do |config|
   # Optional parameter. You can predefine default validation type for
   # Truemail.validate('email@email.com') call without with-parameter
   # Available validation types: :regex, :mx, :smtp
-  config.default_validation_type = :smtp
+  if Rails.env.production?
+    config.default_validation_type = :smtp
+  else
+    config.default_validation_type = :regex
+  end
 
   # Optional parameter. You can predefine which type of validation will be used for domains.
   # Also you can skip validation by domain. Available validation types: :regex, :mx, :smtp
@@ -43,11 +47,6 @@ Truemail.configure do |config|
   # It is equal to empty array by default.
   # config.whitelisted_domains = []
 
-  unless Rails.env.production?
-    config.whitelisted_domains = %w[bestnames.test goodnames.test example.com inbox.test mail.test
-                                    outlook.test invalid.test email.test]
-  end
-
   # Optional parameter. With this option Truemail will validate email which contains whitelisted
   # domain only, i.e. if domain whitelisted, validation will passed to Regex, MX or SMTP validators.
   # Validation of email which not contains whitelisted domain always will return false.