diff --git a/src/standard/config.rs b/src/standard/config.rs
index 63300bab..ace618da 100644
--- a/src/standard/config.rs
+++ b/src/standard/config.rs
@@ -97,6 +97,8 @@ pub struct Config {
 	pub has_base_fee: bool,
 	/// Has PUSH0 opcode. See [EIP-3855](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-3855.md)
 	pub has_push0: bool,
+	/// Enables MCOPY instruction. See [EIP-5656](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-5656.md)
+	pub eip_5656_enabled: bool,
 }
 
 impl Config {
@@ -150,6 +152,7 @@ impl Config {
 			has_ext_code_hash: false,
 			has_base_fee: false,
 			has_push0: false,
+			eip_5656_enabled: false,
 		}
 	}
 
@@ -203,6 +206,7 @@ impl Config {
 			has_ext_code_hash: true,
 			has_base_fee: false,
 			has_push0: false,
+			eip_5656_enabled: false,
 		}
 	}
 
@@ -237,6 +241,7 @@ impl Config {
 			disallow_executable_format,
 			warm_coinbase_address,
 			max_initcode_size,
+			eip_5656_enabled,
 		} = inputs;
 
 		// See https://eips.ethereum.org/EIPS/eip-2929
@@ -299,6 +304,7 @@ impl Config {
 			has_ext_code_hash: true,
 			has_base_fee,
 			has_push0,
+			eip_5656_enabled,
 		}
 	}
 }
@@ -315,6 +321,7 @@ struct DerivedConfigInputs {
 	disallow_executable_format: bool,
 	warm_coinbase_address: bool,
 	max_initcode_size: Option<usize>,
+	eip_5656_enabled: bool,
 }
 
 impl DerivedConfigInputs {
@@ -329,6 +336,7 @@ impl DerivedConfigInputs {
 			disallow_executable_format: false,
 			warm_coinbase_address: false,
 			max_initcode_size: None,
+			eip_5656_enabled: false,
 		}
 	}
 
@@ -343,6 +351,7 @@ impl DerivedConfigInputs {
 			disallow_executable_format: true,
 			warm_coinbase_address: false,
 			max_initcode_size: None,
+			eip_5656_enabled: false,
 		}
 	}
 
@@ -357,6 +366,7 @@ impl DerivedConfigInputs {
 			disallow_executable_format: true,
 			warm_coinbase_address: false,
 			max_initcode_size: None,
+			eip_5656_enabled: false,
 		}
 	}
 
@@ -372,6 +382,7 @@ impl DerivedConfigInputs {
 			warm_coinbase_address: true,
 			// 2 * 24576 as per EIP-3860
 			max_initcode_size: Some(0xC000),
+			eip_5656_enabled: false,
 		}
 	}
 }
diff --git a/src/standard/gasometer/mod.rs b/src/standard/gasometer/mod.rs
index d3d189d2..377d3303 100644
--- a/src/standard/gasometer/mod.rs
+++ b/src/standard/gasometer/mod.rs
@@ -349,7 +349,10 @@ fn dynamic_opcode_cost<H: RuntimeBackend>(
 				len: U256::from_big_endian(&stack.peek(3)?[..]),
 			}
 		}
-		Opcode::CALLDATACOPY | Opcode::CODECOPY | Opcode::MCOPY => GasCost::VeryLowCopy {
+		Opcode::MCOPY if config.eip_5656_enabled => GasCost::VeryLowCopy {
+			len: U256::from_big_endian(&stack.peek(2)?[..]),
+		},
+		Opcode::CALLDATACOPY | Opcode::CODECOPY => GasCost::VeryLowCopy {
 			len: U256::from_big_endian(&stack.peek(2)?[..]),
 		},
 		Opcode::EXP => GasCost::Exp {