diff --git a/src/organisation/schemas.py b/src/organisation/schemas.py
index 3620e38..c34ef16 100644
--- a/src/organisation/schemas.py
+++ b/src/organisation/schemas.py
@@ -8,7 +8,7 @@ Models follow the nomenclature of:
 """
 from typing import Optional
 
-from pydantic import EmailStr, ConfigDict
+from pydantic import EmailStr, ConfigDict, Field
 
 from src.schemas import CustomBaseModel
 from src.contact.schemas import ContactModel
@@ -23,7 +23,7 @@ class Questionnaire(CustomBaseModel):
 	question_three: Optional[str] = None
 
 class OrgIDMixin(CustomBaseModel):
-	organisation_id: int
+	organisation_id: int = Field(gt=0)
 
 
 class OrgPostOrgRequest(CustomBaseModel):