diff --git a/protob/messages-ethereum.proto b/protob/messages-ethereum.proto
index 7ff9010b8..af9b0a263 100644
--- a/protob/messages-ethereum.proto
+++ b/protob/messages-ethereum.proto
@@ -38,6 +38,7 @@ message EthereumPublicKey {
 message EthereumGetAddress {
     repeated uint32 address_n = 1;  // BIP-32 path to derive the key from master node
     optional bool show_display = 2; // optionally show on display before sending the result
+    optional uint32 chain_id = 3;   // Chain Id for EIP 155
 }
 
 /**