diff --git a/modules/nw-operator-cr.adoc b/modules/nw-operator-cr.adoc
index 8a377e89e75e..80a09394962f 100644
--- a/modules/nw-operator-cr.adoc
+++ b/modules/nw-operator-cr.adoc
@@ -49,7 +49,7 @@ The CNO configuration inherits the following fields during cluster installation
 ifdef::post-install-network-configuration,operator[]
 [NOTE]
 ====
-After cluster installation, you can only modify the `clusterNetwork` IP address range.
+After cluster installation, you can only modify the `clusterNetwork` IP address range. The `serviceNetwork` range cannot be modified post-installation. Although the `ServiceCIDR` API is present in the cluster and documented in the {product-title} API reference, the Cluster Network Operator blocks creation or modification of `ServiceCIDR` objects by using a `ValidatingAdmissionPolicy`.
 ====
 endif::[]
 
diff --git a/networking/configuring_network_settings/configuring-cluster-network-range.adoc b/networking/configuring_network_settings/configuring-cluster-network-range.adoc
index 48b08c40d7f4..37ffb013f67a 100644
--- a/networking/configuring_network_settings/configuring-cluster-network-range.adoc
+++ b/networking/configuring_network_settings/configuring-cluster-network-range.adoc
@@ -17,6 +17,11 @@ The following limitations apply when modifying the cluster network IP address ra
 - The host prefix cannot be modified
 - Pods that are configured with an overridden default gateway must be recreated after the cluster network expands
 
+[IMPORTANT]
+====
+Expanding the service network CIDR range after cluster installation is not supported. Although the `ServiceCIDR` API (`servicecidrs.networking.k8s.io`) is present in the cluster and documented in the {product-title} API reference, the Cluster Network Operator deploys a `ValidatingAdmissionPolicy` that blocks creation or modification of `ServiceCIDR` objects. You must configure the service network CIDR during installation by using the `install-config.yaml` file. To avoid service IP address exhaustion, ensure that your initial service network range is large enough to accommodate future growth.
+====
+
 include::modules/nw-cluster-network-range-edit.adoc[leveloffset=+1]
 
 [role="_additional-resources"]