diff --git a/packages/config-registry-controller/CHANGELOG.md b/packages/config-registry-controller/CHANGELOG.md
index f78e83636aa..f5cab6f568e 100644
--- a/packages/config-registry-controller/CHANGELOG.md
+++ b/packages/config-registry-controller/CHANGELOG.md
@@ -10,12 +10,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Add `ConfigRegistryControllerStateChangedEvent` (`ConfigRegistryController:stateChanged`) to the controller's events ([#9595](https://github.com/MetaMask/core/pull/9595))
-- Add `ConfigRegistryController.getNetworkConfigByCaip2ChainId` method to retrieve a network config by its CAIP-2 chain ID ([#9597](https://github.com/MetaMask/core/pull/9597))
+- Add `ConfigRegistryController.getNetworkConfigByCaip2ChainId` method to retrieve a network config by its CAIP-2 chain ID ([#9597](https://github.com/MetaMask/core/pull/9597), [#9606](https://github.com/MetaMask/core/pull/9606))
   - The method returns the network config if found, or `undefined` if not found.
   - The method is also accessible via the controller's messenger as `ConfigRegistryController:getNetworkConfigByCaip2ChainId`.
 
 ### Changed
 
+- **BREAKING:** `ConfigRegistryControllerState.configs.networks` is now a `Record<Caip2ChainId, RegistryNetworkConfig>` instead of a `Record<string, RegistryNetworkConfig>` ([#9606](https://github.com/MetaMask/core/pull/9606))
 - Bump `@metamask/utils` from `^11.9.0` to `^11.11.0` ([#9074](https://github.com/MetaMask/core/pull/9074))
 - Bump `@metamask/controller-utils` from `^12.1.1` to `^12.3.0` ([#9083](https://github.com/MetaMask/core/pull/9083), [#9218](https://github.com/MetaMask/core/pull/9218))
 - Bump `@metamask/profile-sync-controller` from `^28.1.1` to `^28.3.0` ([#9119](https://github.com/MetaMask/core/pull/9119), [#9463](https://github.com/MetaMask/core/pull/9463))
diff --git a/packages/config-registry-controller/src/ConfigRegistryController.ts b/packages/config-registry-controller/src/ConfigRegistryController.ts
index 2903f8ce5fa..3348a65a833 100644
--- a/packages/config-registry-controller/src/ConfigRegistryController.ts
+++ b/packages/config-registry-controller/src/ConfigRegistryController.ts
@@ -12,7 +12,7 @@ import type { Messenger } from '@metamask/messenger';
 import { StaticIntervalPollingController } from '@metamask/polling-controller';
 import type { RemoteFeatureFlagControllerGetStateAction } from '@metamask/remote-feature-flag-controller';
 import type { RemoteFeatureFlagControllerStateChangeEvent } from '@metamask/remote-feature-flag-controller';
-import { Duration, inMilliseconds, Json } from '@metamask/utils';
+import { CaipChainId, Duration, inMilliseconds, Json } from '@metamask/utils';
 
 import type { ConfigRegistryApiServiceFetchConfigAction } from './config-registry-api-service/config-registry-api-service-method-action-types.js';
 import type { RegistryNetworkConfig } from './config-registry-api-service/types.js';
@@ -37,7 +37,7 @@ export type ConfigRegistryControllerState = {
    * Use selectors (e.g. selectFeaturedNetworks) to filter when needed.
    */
   configs: {
-    networks: Record<string, RegistryNetworkConfig>;
+    networks: Record<CaipChainId, RegistryNetworkConfig>;
   };
   /**
    * Semantic version string of the configuration data from the API.
@@ -216,7 +216,7 @@ export class ConfigRegistryController extends StaticIntervalPollingController<nu
    * @returns The network configuration if found, otherwise undefined.
    */
   getNetworkConfigByCaip2ChainId(
-    caip2ChainId: string,
+    caip2ChainId: CaipChainId,
   ): RegistryNetworkConfig | undefined {
     return this.state.configs.networks[caip2ChainId];
   }
diff --git a/packages/config-registry-controller/src/config-registry-api-service/types.ts b/packages/config-registry-controller/src/config-registry-api-service/types.ts
index 4cc5ecdbbe5..f7eb1628ea7 100644
--- a/packages/config-registry-controller/src/config-registry-api-service/types.ts
+++ b/packages/config-registry-controller/src/config-registry-api-service/types.ts
@@ -8,6 +8,7 @@ import {
   string,
   type,
 } from '@metamask/superstruct';
+import { CaipChainIdStruct } from '@metamask/utils';
 
 const AssetSchema = type({
   assetId: string(),
@@ -55,7 +56,7 @@ const ChainConfigSchema = type({
  * chainId is in CAIP-2 format (e.g. "eip155:1", "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp").
  */
 export const RegistryNetworkConfigSchema = type({
-  chainId: string(),
+  chainId: CaipChainIdStruct,
   name: string(),
   imageUrl: string(),
   coingeckoPlatformId: string(),