diff --git a/ethcore/machine/src/executive.rs b/ethcore/machine/src/executive.rs
index 119780f6358..d1c8fa08b31 100644
--- a/ethcore/machine/src/executive.rs
+++ b/ethcore/machine/src/executive.rs
@@ -2283,7 +2283,7 @@ mod tests {
 
 		let mut info = EnvInfo::default();
 
-		// 100 > 10
+		// 200 (wasmDisableTransition) > 100 > 10 (wasmActivationTransition)
 		info.number = 100;
 
 		// Network with wasm activated at block 10
@@ -2301,19 +2301,34 @@ mod tests {
 		// Transaction successfully returned sender
 		assert_eq!(output[..], sender[..]);
 
-		// 1 < 10
+		// 1 < 10 (wasmActivationTransition)
 		info.number = 1;
 
 		let mut output = [0u8; 20];
 		let FinalizationResult { gas_left: result, return_data, .. } = {
 			let schedule = machine.schedule(info.number);
 			let mut ex = Executive::new(&mut state, &info, &machine, &schedule);
-			ex.call(params, &mut Substate::new(), &mut NoopTracer, &mut NoopVMTracer).unwrap()
+			ex.call(params.clone(), &mut Substate::new(), &mut NoopTracer, &mut NoopVMTracer).unwrap()
 		};
 		(&mut output[..((cmp::min(20, return_data.len())))]).copy_from_slice(&return_data[..(cmp::min(20, return_data.len()))]);
 
 		assert_eq!(result, U256::from(20025));
 		// Since transaction errored due to wasm was not activated, result is just empty
 		assert_eq!(output[..], [0u8; 20][..]);
+
+		// 200 == wasmDisableTransition
+		info.number = 200;
+
+		let mut output = [0u8; 20];
+		let FinalizationResult { gas_left: result, return_data, .. } = {
+			let schedule = machine.schedule(info.number);
+			let mut ex = Executive::new(&mut state, &info, &machine, &schedule);
+			ex.call(params, &mut Substate::new(), &mut NoopTracer, &mut NoopVMTracer).unwrap()
+		};
+		(&mut output[..((cmp::min(20, return_data.len())))]).copy_from_slice(&return_data[..(cmp::min(20, return_data.len()))]);
+
+		assert_eq!(result, U256::from(20025));
+		// Since transaction errored due to wasm was deactivated, result is just empty
+		assert_eq!(output[..], [0u8; 20][..]);
 	}
 }
diff --git a/ethcore/res/ethereum/test-specs/kovan_wasm_test.json b/ethcore/res/ethereum/test-specs/kovan_wasm_test.json
index 70143d8a8de..a393cfb5eac 100644
--- a/ethcore/res/ethereum/test-specs/kovan_wasm_test.json
+++ b/ethcore/res/ethereum/test-specs/kovan_wasm_test.json
@@ -42,7 +42,8 @@
 		"eip211Transition": 5067000,
 		"eip214Transition": 5067000,
 		"eip658Transition": 5067000,
-		"wasmActivationTransition": 10
+		"wasmActivationTransition": 10,
+		"wasmDisableTransition": 200
 	},
 	"genesis": {
 		"seal": {
diff --git a/ethcore/spec/src/spec.rs b/ethcore/spec/src/spec.rs
index 2baeb5ca40f..8202403dd88 100644
--- a/ethcore/spec/src/spec.rs
+++ b/ethcore/spec/src/spec.rs
@@ -411,6 +411,7 @@ impl Spec {
 			params.eip2315_transition,
 			params.dust_protection_transition,
 			params.wasm_activation_transition,
+			params.wasm_disable_transition,
 			params.kip4_transition,
 			params.kip6_transition,
 			params.max_code_size_transition,
diff --git a/ethcore/types/src/engines/params.rs b/ethcore/types/src/engines/params.rs
index c05f5f355b2..5265c9c5da0 100644
--- a/ethcore/types/src/engines/params.rs
+++ b/ethcore/types/src/engines/params.rs
@@ -114,6 +114,8 @@ pub struct CommonParams {
 	pub remove_dust_contracts: bool,
 	/// Wasm activation blocknumber, if any disabled initially.
 	pub wasm_activation_transition: BlockNumber,
+	/// Wasm deactivation blocknumber, if enabled.
+	pub wasm_disable_transition: BlockNumber,
 	/// Wasm account version, activated after `wasm_activation_transition`. If this field is defined, do not use code
 	/// prefix to determine VM to execute.
 	pub wasm_version: Option<U256>,
@@ -208,7 +210,7 @@ impl CommonParams {
 				false => vm::CleanDustMode::BasicOnly,
 			};
 		}
-		if block_number >= self.wasm_activation_transition {
+		if block_number >= self.wasm_activation_transition && block_number < self.wasm_disable_transition {
 			let mut wasm = vm::WasmCosts::default();
 			if block_number >= self.kip4_transition {
 				wasm.have_create2 = true;
@@ -367,6 +369,10 @@ impl From<ethjson::spec::Params> for CommonParams {
 				BlockNumber::max_value,
 				Into::into
 			),
+			wasm_disable_transition: p.wasm_disable_transition.map_or_else(
+				BlockNumber::max_value,
+				Into::into
+			),
 			wasm_version: p.wasm_version.map(Into::into),
 			kip4_transition: p.kip4_transition.map_or_else(
 				BlockNumber::max_value,
diff --git a/json/src/spec/params.rs b/json/src/spec/params.rs
index 575f2c0c5a0..b11fb22cbdf 100644
--- a/json/src/spec/params.rs
+++ b/json/src/spec/params.rs
@@ -139,6 +139,8 @@ pub struct Params {
 	pub transaction_permission_contract_transition: Option<Uint>,
 	/// Wasm activation block height, if not activated from start.
 	pub wasm_activation_transition: Option<Uint>,
+	/// Wasm deactivation block height, if activated.
+	pub wasm_disable_transition: Option<Uint>,
 	/// Define a separate wasm version instead of using the prefix.
 	pub wasm_version: Option<Uint>,
 	/// KIP4 activiation block height.
@@ -163,7 +165,8 @@ mod tests {
 			"accountStartNonce": "0x01",
 			"gasLimitBoundDivisor": "0x20",
 			"maxCodeSize": "0x1000",
-			"wasmActivationTransition": "0x1010"
+			"wasmActivationTransition": "0x1010",
+			"wasmDisableTransition": "0x2010"
 		}"#;
 
 		let deserialized: Params = serde_json::from_str(s).unwrap();
@@ -176,6 +179,7 @@ mod tests {
 		assert_eq!(deserialized.gas_limit_bound_divisor, Uint(U256::from(0x20)));
 		assert_eq!(deserialized.max_code_size, Some(Uint(U256::from(0x1000))));
 		assert_eq!(deserialized.wasm_activation_transition, Some(Uint(U256::from(0x1010))));
+		assert_eq!(deserialized.wasm_disable_transition, Some(Uint(U256::from(0x2010))));
 	}
 
 	#[test]