diff --git a/infrastructure/commons/istio/variables.tf b/infrastructure/commons/istio/variables.tf
index 8c034cd2..d9a79606 100644
--- a/infrastructure/commons/istio/variables.tf
+++ b/infrastructure/commons/istio/variables.tf
@@ -5,13 +5,13 @@
 variable "istio_base_version" {
   description = "Helm chart version for the istio-base component"
   type        = string
-  default     = "1.27.1"
+  default     = "1.30.4"
 }
 
 variable "istiod_version" {
   description = "Helm chart version for istiod (Istio control plane)"
   type        = string
-  default     = "1.27.1"
+  default     = "1.30.4"
 }
 
 variable "istiod_replicas" {
diff --git a/nullplatform/base/tests/base_values.tftest.hcl b/nullplatform/base/tests/base_values.tftest.hcl
index ce537d6a..a3becc53 100644
--- a/nullplatform/base/tests/base_values.tftest.hcl
+++ b/nullplatform/base/tests/base_values.tftest.hcl
@@ -13,12 +13,12 @@ variables {
 # Gateway API CRD ref
 ############################################
 
-run "gateway_api_crd_ref_defaults_to_istio_1_27_ref" {
+run "gateway_api_crd_ref_defaults_to_istio_1_30_ref" {
   command = plan
 
   assert {
-    condition     = strcontains(output.rendered_values, "gatewayApiCrdRef: \"v1.3.0\"")
-    error_message = "gatewayApiCrdRef should default to v1.3.0, matching Istio 1.27"
+    condition     = strcontains(output.rendered_values, "gatewayApiCrdRef: \"v1.5.1\"")
+    error_message = "gatewayApiCrdRef should default to v1.5.1, matching Istio 1.30"
   }
 }
 
diff --git a/nullplatform/base/variables.tf b/nullplatform/base/variables.tf
index 7ff11a29..a43f9a45 100644
--- a/nullplatform/base/variables.tf
+++ b/nullplatform/base/variables.tf
@@ -44,8 +44,8 @@ variable "install_gateway_v2_crd" {
 
 variable "gateway_api_crd_ref" {
   type        = string
-  description = "Git ref (tag or commit) of kubernetes-sigs/gateway-api to install when install_gateway_v2_crd is true. Ignored on chart versions older than the one that introduced global.gatewayApiCrdRef. Default (v1.3.0) matches what Istio 1.27 documents installing; re-check istio.io's version-pinned docs when bumping Istio."
-  default     = "v1.3.0"
+  description = "Git ref (tag or commit) of kubernetes-sigs/gateway-api to install when install_gateway_v2_crd is true. Ignored on chart versions older than the one that introduced global.gatewayApiCrdRef. Default (v1.5.1) matches what Istio 1.30 documents installing; re-check istio.io's version-pinned docs when bumping Istio. Istio 1.30's own release notes warn that upgrading without also upgrading these CRDs leaves TLSRoute/ReferenceGrant invisible to istiod."
+  default     = "v1.5.1"
 }
 
 ############################################