diff --git a/api/v1/swagger/definitions/patron.yaml b/api/v1/swagger/definitions/patron.yaml
index 6e99899afd..afb252e1f1 100644
--- a/api/v1/swagger/definitions/patron.yaml
+++ b/api/v1/swagger/definitions/patron.yaml
@@ -407,6 +407,7 @@ properties:
       - string
       - "null"
     description: patron's primary contact method
+    maxLength: 45
   _strings:
     type:
       - object