diff --git a/app/controllers/api/v1/registrant/contacts_controller.rb b/app/controllers/api/v1/registrant/contacts_controller.rb
index f252b3acd..2c8a1f70e 100644
--- a/app/controllers/api/v1/registrant/contacts_controller.rb
+++ b/app/controllers/api/v1/registrant/contacts_controller.rb
@@ -1,6 +1,3 @@
-require 'rails5_api_controller_backport'
-require 'auth_token/auth_token_decryptor'
-
 module Api
   module V1
     module Registrant
@@ -39,7 +36,20 @@ module Api
 
         def set_contacts_pool
           country_code, ident = current_user.registrant_ident.to_s.split '-'
-          @contacts_pool = Contact.where(country_code: country_code, ident: ident)
+          associated_domain_ids = begin
+            BusinessRegistryCache.fetch_by_ident_and_cc(ident, country_code).associated_domain_ids
+          end
+
+          available_contacts_ids = begin
+            DomainContact.where(domain_id: associated_domain_ids).pluck(:contact_id) |
+              Domain.where(id: associated_domain_ids).pluck(:registrant_id)
+          end
+
+          @contacts_pool = Contact.where(id: available_contacts_ids)
+        rescue Soap::Arireg::NotAvailableError => error
+          Rails.logger.fatal("[EXCEPTION] #{error}")
+          render json: { errors: [{ base: ["Business Registry Not Available"] }] },
+                 status: :service_unavailable and return
         end
       end
     end
diff --git a/app/controllers/api/v1/registrant/domains_controller.rb b/app/controllers/api/v1/registrant/domains_controller.rb
index 27b7b6125..7209f8a10 100644
--- a/app/controllers/api/v1/registrant/domains_controller.rb
+++ b/app/controllers/api/v1/registrant/domains_controller.rb
@@ -1,5 +1,3 @@
-require 'rails5_api_controller_backport'
-
 module Api
   module V1
     module Registrant
diff --git a/app/controllers/registrant/contacts_controller.rb b/app/controllers/registrant/contacts_controller.rb
index f73650de2..267b4d68d 100644
--- a/app/controllers/registrant/contacts_controller.rb
+++ b/app/controllers/registrant/contacts_controller.rb
@@ -26,4 +26,4 @@ class Registrant::ContactsController < RegistrantController
       BusinessRegistryCache.fetch_by_ident_and_cc(ident, ident_cc).associated_domain_ids
     end
   end
-end
\ No newline at end of file
+end
diff --git a/test/integration/api/registrant/registrant_api_contacts_test.rb b/test/integration/api/registrant/registrant_api_contacts_test.rb
index c73c4a503..28dd50d76 100644
--- a/test/integration/api/registrant/registrant_api_contacts_test.rb
+++ b/test/integration/api/registrant/registrant_api_contacts_test.rb
@@ -5,19 +5,30 @@ class RegistrantApiContactsTest < ApplicationIntegrationTest
   def setup
     super
 
+    @original_registry_time = Setting.days_to_keep_business_registry_cache
+    Setting.days_to_keep_business_registry_cache = 1
+    travel_to Time.zone.parse('2010-07-05')
+
     @user = users(:registrant)
     @auth_headers = { 'HTTP_AUTHORIZATION' => auth_token }
   end
 
+  def teardown
+    super
+
+    Setting.days_to_keep_business_registry_cache = @original_registry_time
+    travel_back
+  end
+
   def test_root_returns_domain_list
     get '/api/v1/registrant/contacts', {}, @auth_headers
     assert_equal(200, response.status)
 
     json_body = JSON.parse(response.body, symbolize_names: true)
-    assert_equal(2, json_body.count)
+    assert_equal(5, json_body.count)
     array_of_contact_codes = json_body.map { |x| x[:code] }
     assert(array_of_contact_codes.include?('william-001'))
-    assert(array_of_contact_codes.include?('william-002'))
+    assert(array_of_contact_codes.include?('jane-001'))
   end
 
   def test_root_accepts_limit_and_offset_parameters
@@ -28,7 +39,23 @@ class RegistrantApiContactsTest < ApplicationIntegrationTest
 
     get '/api/v1/registrant/contacts', {}, @auth_headers
     response_json = JSON.parse(response.body, symbolize_names: true)
-    assert_equal(2, response_json.count)
+    assert_equal(5, response_json.count)
+  end
+
+  def test_get_contact_details_by_uuid
+    get '/api/v1/registrant/contacts/0aa54704-d6f7-4ca9-b8ca-2827d9a4e4eb', {}, @auth_headers
+    assert_equal(200, response.status)
+
+    contact = JSON.parse(response.body, symbolize_names: true)
+    assert_equal('william@inbox.test', contact[:email])
+  end
+
+  def test_get_contact_details_by_uuid_returns_404_for_non_existent_contact
+    get '/api/v1/registrant/contacts/nonexistent-uuid', {}, @auth_headers
+    assert_equal(404, response.status)
+
+    response_json = JSON.parse(response.body, symbolize_names: true)
+    assert_equal({ errors: [{ base: ['Contact not found'] }] }, response_json)
   end
 
   def test_root_does_not_accept_limit_higher_than_200