diff --git a/src/lib/dataEntities/networks.ts b/src/lib/dataEntities/networks.ts
index abea1cddd..1b3744f27 100644
--- a/src/lib/dataEntities/networks.ts
+++ b/src/lib/dataEntities/networks.ts
@@ -66,6 +66,10 @@ export interface ArbitrumNetwork {
    * In case of a chain that uses an ERC-20 token from the parent chain as its native/gas token, this is the address of said token on the parent chain
    */
   nativeToken?: string
+  /**
+   * Whether or not it is a testnet chain.
+   */
+  isTestnet: boolean
   /**
    * Whether or not the chain was registered by the user.
    */
@@ -197,6 +201,7 @@ const networks: {
     },
     confirmPeriodBlocks: 45818,
     isCustom: false,
+    isTestnet: false,
   },
   42170: {
     chainId: 42170,
@@ -209,6 +214,7 @@ const networks: {
       sequencerInbox: '0x211E1c4c7f1bF5351Ac850Ed10FD68CFfCF6c21b',
     },
     isCustom: false,
+    isTestnet: false,
     name: 'Arbitrum Nova',
     parentChainId: 1,
     tokenBridge: {
@@ -243,6 +249,7 @@ const networks: {
       sequencerInbox: '0x6c97864CE4bEf387dE0b3310A44230f7E3F1be0D',
     },
     isCustom: false,
+    isTestnet: true,
     name: 'Arbitrum Rollup Sepolia Testnet',
     parentChainId: 11155111,
     tokenBridge: {