diff --git a/models/staging/xero/schema.yml b/models/staging/xero/schema.yml
index 7a89a51..8f7af29 100644
--- a/models/staging/xero/schema.yml
+++ b/models/staging/xero/schema.yml
@@ -10,6 +10,9 @@ models:
       - name: id_contact
         data_type: character varying
         description: Xero's unique identifier for the contact.
+        tests:
+          - not_null
+          - unique
 
       - name: account_number
         data_type: character varying
@@ -18,14 +21,29 @@ models:
       - name: contact_name
         data_type: character varying
         description: The name for the customer.
+        tests:
+          - not_null
+          - unique
 
       - name: is_customer
         data_type: boolean
         description: Flag that shows if the contact is a Superhog customer.
+        tests:
+          - not_null
+          - accepted_values:
+              values:
+                - true
+                - false
 
       - name: is_supplier
         data_type: boolean
         description: Flag that shows if the contact is a Superhog supplier.
+        tests:
+          - not_null
+          - accepted_values:
+              values:
+                - true
+                - false
 
       - name: tax_number
         data_type: character varying