diff --git a/mmv1/products/compute/RouterNat.yaml b/mmv1/products/compute/RouterNat.yaml
index 9b0d414391a1..fef5eb3398c2 100644
--- a/mmv1/products/compute/RouterNat.yaml
+++ b/mmv1/products/compute/RouterNat.yaml
@@ -236,7 +236,8 @@ properties:
   - !ruby/object:Api::Type::Integer
     name: minPortsPerVm
     description: |
-      Minimum number of ports allocated to a VM from this NAT.
+      Minimum number of ports allocated to a VM from this NAT. Defaults to 64 for static port allocation and 32 dynamic port allocation if not set.
+    default_from_api: true
   - !ruby/object:Api::Type::Integer
     name: maxPortsPerVm
     description: |