diff --git a/consensus/state_processing/src/genesis.rs b/consensus/state_processing/src/genesis.rs
index b5a3c24e70..01c6102af1 100644
--- a/consensus/state_processing/src/genesis.rs
+++ b/consensus/state_processing/src/genesis.rs
@@ -71,7 +71,7 @@ pub fn initialize_beacon_state_from_eth1<T: EthSpec>(
             timestamp: eth1_timestamp,
             random: eth1_block_hash,
             gas_limit: GENESIS_GAS_LIMIT,
-            base_fee_per_gas: GENESIS_BASE_FEE_PER_GAS,
+            base_fee_per_gas: Uint256::from_little_endian(&GENESIS_BASE_FEE_PER_GAS),
             ..ExecutionPayloadHeader::default()
         };
     }
diff --git a/consensus/types/src/consts.rs b/consensus/types/src/consts.rs
index 6088086ca5..2fc861f552 100644
--- a/consensus/types/src/consts.rs
+++ b/consensus/types/src/consts.rs
@@ -21,11 +21,10 @@ pub mod altair {
 }
 
 pub mod merge_testing {
-    use ethereum_types::H256;
     pub const GENESIS_GAS_LIMIT: u64 = 30_000_000;
-    pub const GENESIS_BASE_FEE_PER_GAS: H256 = H256([
+    pub const GENESIS_BASE_FEE_PER_GAS: [u8; 32] = [
         0x00, 0xca, 0x9a, 0x3b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
         0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
         0x00, 0x00,
-    ]);
+    ];
 }
diff --git a/consensus/types/src/execution_payload.rs b/consensus/types/src/execution_payload.rs
index 688d123900..e6d8f7e2dd 100644
--- a/consensus/types/src/execution_payload.rs
+++ b/consensus/types/src/execution_payload.rs
@@ -59,7 +59,7 @@ pub struct ExecutionPayload<T: EthSpec> {
     pub timestamp: u64,
     #[serde(with = "ssz_types::serde_utils::hex_var_list")]
     pub extra_data: VariableList<u8, T::MaxExtraDataBytes>,
-    pub base_fee_per_gas: Hash256,
+    pub base_fee_per_gas: Uint256,
     pub block_hash: Hash256,
     #[test_random(default)]
     pub transactions: VariableList<Transaction<T>, T::MaxTransactionsPerPayload>,
@@ -80,7 +80,7 @@ impl<T: EthSpec> ExecutionPayload<T> {
             gas_used: 0,
             timestamp: 0,
             extra_data: VariableList::empty(),
-            base_fee_per_gas: Hash256::zero(),
+            base_fee_per_gas: Uint256::zero(),
             block_hash: Hash256::zero(),
             transactions: VariableList::empty(),
         }
diff --git a/consensus/types/src/execution_payload_header.rs b/consensus/types/src/execution_payload_header.rs
index e9876d89b9..4ed2aec016 100644
--- a/consensus/types/src/execution_payload_header.rs
+++ b/consensus/types/src/execution_payload_header.rs
@@ -26,7 +26,7 @@ pub struct ExecutionPayloadHeader<T: EthSpec> {
     pub timestamp: u64,
     #[serde(with = "ssz_types::serde_utils::hex_var_list")]
     pub extra_data: VariableList<u8, T::MaxExtraDataBytes>,
-    pub base_fee_per_gas: Hash256,
+    pub base_fee_per_gas: Uint256,
     pub block_hash: Hash256,
     pub transactions_root: Hash256,
 }