diff --git a/k8s/deployment/build_context b/k8s/deployment/build_context
index 370287e8..4f14edbd 100755
--- a/k8s/deployment/build_context
+++ b/k8s/deployment/build_context
@@ -287,7 +287,7 @@ CONTEXT=$(echo "$CONTEXT" | jq '
 MAIN_TRAFFIC_MANAGER_PORT=$(get_config_value \
   --env MAIN_TRAFFIC_MANAGER_PORT \
   --provider '.providers["scope-configurations"].deployment.main_traffic_manager_port' \
-  --provider '.providers["container-orchestration"].cluster.main_traffic_manager_port' \
+  --provider '.providers["container-orchestration"].traffic_manager.port' \
   --default "80"
 )
 
diff --git a/k8s/deployment/tests/build_context.bats b/k8s/deployment/tests/build_context.bats
index 09605911..3067f988 100644
--- a/k8s/deployment/tests/build_context.bats
+++ b/k8s/deployment/tests/build_context.bats
@@ -1064,7 +1064,7 @@ set_capabilities() {
 
 @test "main_traffic_manager_port: read from container-orchestration provider" {
   setup_full_build_context
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = 10080')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = 10080')
 
   source "$SCRIPT"
 
@@ -1074,7 +1074,7 @@ set_capabilities() {
 @test "main_traffic_manager_port: scope-configurations takes priority over container-orchestration" {
   setup_full_build_context
   CONTEXT=$(echo "$CONTEXT" | jq '
-    .providers["container-orchestration"].cluster.main_traffic_manager_port = 10080
+    .providers["container-orchestration"].traffic_manager.port = 10080
     | .providers["scope-configurations"].deployment.main_traffic_manager_port = 11080
   ')
 
@@ -1094,7 +1094,7 @@ set_capabilities() {
 
 @test "main_traffic_manager_port: rejects non-numeric value" {
   setup_full_build_context
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = "not-a-port"')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = "not-a-port"')
 
   run source "$SCRIPT"
 
@@ -1112,7 +1112,7 @@ EOF
 
 @test "main_traffic_manager_port: accepts a privileged port other than 80" {
   setup_full_build_context
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = 90')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = 90')
 
   source "$SCRIPT"
 
@@ -1121,7 +1121,7 @@ EOF
 
 @test "main_traffic_manager_port: rejects port above 65535" {
   setup_full_build_context
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = 70000')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = 70000')
 
   run source "$SCRIPT"
 
@@ -1139,7 +1139,7 @@ EOF
 
 @test "main_traffic_manager_port: rejects port 0" {
   setup_full_build_context
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = 0')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = 0')
 
   run source "$SCRIPT"
 
@@ -1159,7 +1159,7 @@ EOF
   setup_full_build_context
   CONTEXT=$(echo "$CONTEXT" | jq '
     .scope.capabilities.main_http_port = 10080
-    | .providers["container-orchestration"].cluster.main_traffic_manager_port = 10080
+    | .providers["container-orchestration"].traffic_manager.port = 10080
   ')
 
   run source "$SCRIPT"
@@ -1181,7 +1181,7 @@ EOF
 @test "main_traffic_manager_port: rejects collision with an additional port" {
   setup_full_build_context
   set_additional_ports '[{"port":10080,"type":"HTTP"}]'
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = 10080')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = 10080')
 
   run source "$SCRIPT"
 
@@ -1202,7 +1202,7 @@ EOF
 @test "main_traffic_manager_port: rejects collision with an additional port's sidecar port" {
   setup_full_build_context
   set_additional_ports '[{"port":8081,"type":"HTTP"}]'
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = 18081')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = 18081')
 
   run source "$SCRIPT"
 
@@ -1223,7 +1223,7 @@ EOF
 @test "main_traffic_manager_port: accepts 10080 alongside unrelated additional ports" {
   setup_full_build_context
   set_additional_ports '[{"port":9090,"type":"HTTP"},{"port":9014,"type":"GRPC"}]'
-  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].cluster.main_traffic_manager_port = 10080')
+  CONTEXT=$(echo "$CONTEXT" | jq '.providers["container-orchestration"].traffic_manager.port = 10080')
 
   source "$SCRIPT"
 
diff --git a/k8s/docs/configurable-http-ports.md b/k8s/docs/configurable-http-ports.md
index 9cb1d6c3..47d162c7 100644
--- a/k8s/docs/configurable-http-ports.md
+++ b/k8s/docs/configurable-http-ports.md
@@ -34,7 +34,9 @@ The port your application binds to inside the container. When set, the following
 - **Default:** `80`
 - **Valid values:** `1`–`65535`
 - **Configured via:** `container-orchestration` provider at
-  `.cluster.main_traffic_manager_port`, the `scope-configurations` provider at
+  `.traffic_manager.port` (exposed in the EKS provider spec as the
+  `Traffic Manager Port` field, mapped to the NRN key
+  `k8s.mainTrafficManagerPort`), the `scope-configurations` provider at
   `.deployment.main_traffic_manager_port`, or the `MAIN_TRAFFIC_MANAGER_PORT`
   env var in `values.yaml`. Precedence follows the usual order —
   `scope-configurations`, then `container-orchestration`, then env, then default.
@@ -77,7 +79,8 @@ To adopt a different port, in this order:
 
 1. Allow the port (`10080` recommended) inbound on the security group attached
    to the pod ENIs.
-2. Set `main_traffic_manager_port` in the `container-orchestration` provider.
+2. Set `traffic_manager.port` in the `container-orchestration` provider (the
+   `Traffic Manager Port` field on the EKS provider).
 3. Deploy.
 
 The order matters. Setting the knob before opening the port yields a green