diff --git a/l1-contracts/.env b/l1-contracts/.env
index 9d28b0c92..a55f1264e 100644
--- a/l1-contracts/.env
+++ b/l1-contracts/.env
@@ -2,7 +2,7 @@ CHAIN_ETH_NETWORK=hardhat
 CONTRACTS_PRIORITY_TX_MAX_GAS_LIMIT=72000000
 CONTRACTS_DEPLOY_L2_BRIDGE_COUNTERPART_GAS_LIMIT=10000000
 ETH_CLIENT_WEB3_URL=http://127.0.0.1:8545
-CHAIN_ETH_ZKSYNC_NETWORK_ID=270
+CHAIN_ETH_ZKSYNC_NETWORK_ID=271
 CONTRACTS_BRIDGEHUB_PROXY_ADDR=0x0000000000000000000000000000000000000000
 CONTRACTS_BRIDGEHUB_IMPL_ADDR=0x0000000000000000000000000000000000000000
 CONTRACTS_STATE_TRANSITION_PROXY_ADDR=0x0000000000000000000000000000000000000000
diff --git a/l1-contracts/test/unit_tests/mailbox_test.spec.ts b/l1-contracts/test/unit_tests/mailbox_test.spec.ts
index 6a2788a98..681677385 100644
--- a/l1-contracts/test/unit_tests/mailbox_test.spec.ts
+++ b/l1-contracts/test/unit_tests/mailbox_test.spec.ts
@@ -33,7 +33,7 @@ describe("Mailbox tests", function () {
   let bridgehub: Bridgehub;
   let owner: ethers.Signer;
   let forwarder: Forwarder;
-  let chainId = process.env.CHAIN_ETH_ZKSYNC_NETWORK_ID || 270;
+  let chainId = process.env.CHAIN_ETH_ZKSYNC_NETWORK_ID || 271;
 
   before(async () => {
     [owner] = await hardhat.ethers.getSigners();