diff --git a/contracts/src/core/MachServiceManagerStorage.sol b/contracts/src/core/MachServiceManagerStorage.sol
index ef7a0f8..18b15be 100644
--- a/contracts/src/core/MachServiceManagerStorage.sol
+++ b/contracts/src/core/MachServiceManagerStorage.sol
@@ -31,7 +31,10 @@ abstract contract MachServiceManagerStorage {
     /// @notice Minimul quorum threshold percentage
     uint8 public quorumThresholdPercentage;
 
+    /// @notice Chain id
+    uint256 public immutable chainId;
+
     // storage gap for upgradeability
     // slither-disable-next-line shadowing-state
-    uint256[46] private __GAP;
+    uint256[45] private __GAP;
 }