diff --git a/models/intermediate/xero/schema.yml b/models/intermediate/xero/schema.yml
index 3278fa9..9094f61 100644
--- a/models/intermediate/xero/schema.yml
+++ b/models/intermediate/xero/schema.yml
@@ -31,6 +31,8 @@ models:
         data_type: character varying
         description: |
           Identifier of the account. It can be null.
+        data_tests:
+          - unique
 
       - name: is_contact_missing_id_deal
         data_type: boolean
diff --git a/models/reporting/xero/schema.yml b/models/reporting/xero/schema.yml
index 207cc0d..6255a62 100644
--- a/models/reporting/xero/schema.yml
+++ b/models/reporting/xero/schema.yml
@@ -296,6 +296,9 @@ models:
       - name: id_contact
         data_type: character varying
         description: Xero's unique identifier for the contact.
+        data_tests:
+          - not_null
+          - unique
 
       - name: account_number
         data_type: character varying
@@ -309,6 +312,8 @@ models:
 
           You can use this to find specific deal ids or even as a proxy bool to
           keep or remove deal id customers.
+        data_tests:
+          - unique
 
       - name: contact_name
         data_type: character varying