diff --git a/crates/primitives/src/transaction/eip1559.rs b/crates/primitives/src/transaction/eip1559.rs
index 02ff1ec499..43f9e0db68 100644
--- a/crates/primitives/src/transaction/eip1559.rs
+++ b/crates/primitives/src/transaction/eip1559.rs
@@ -10,7 +10,7 @@ use std::mem;
 #[derive(Debug, Clone, PartialEq, Eq, Hash, Default)]
 pub struct TxEip1559 {
     /// Added as EIP-pub 155: Simple replay attack protection
-    pub chain_id: u64,
+    pub chain_id: ChainId,
     /// A scalar value equal to the number of transactions sent by the sender; formally Tn.
     pub nonce: u64,
     /// A scalar value equal to the maximum
diff --git a/crates/primitives/src/transaction/eip4844.rs b/crates/primitives/src/transaction/eip4844.rs
index ce15de52af..87d9cee9e0 100644
--- a/crates/primitives/src/transaction/eip4844.rs
+++ b/crates/primitives/src/transaction/eip4844.rs
@@ -24,7 +24,7 @@ use std::ops::Deref;
 #[derive(Debug, Clone, PartialEq, Eq, Hash, Default)]
 pub struct TxEip4844 {
     /// Added as EIP-pub 155: Simple replay attack protection
-    pub chain_id: u64,
+    pub chain_id: ChainId,
     /// A scalar value equal to the number of transactions sent by the sender; formally Tn.
     pub nonce: u64,
     /// A scalar value equal to the maximum