diff --git a/lib/opFns.js b/lib/opFns.js
index 993cfadd59..de0def4403 100644
--- a/lib/opFns.js
+++ b/lib/opFns.js
@@ -258,7 +258,7 @@ module.exports = {
     return new BN(runState.lastReturned.length)
   },
   RETURNDATACOPY: function (memOffset, returnDataOffset, length, runState) {
-    if ((returnDataOffset.add(length)).gt(new BN(runState.lastReturned.length))) {
+    if ((returnDataOffset.add(length)).gtn(runState.lastReturned.length)) {
       trap(ERROR.OUT_OF_GAS)
     }
 
@@ -346,7 +346,7 @@ module.exports = {
           subGas(runState, new BN(fees.sstoreResetGas.v))
         } else if (value.length === 0 && found.length) {
           subGas(runState, new BN(fees.sstoreResetGas.v))
-          runState.gasRefund.iadd(new BN(fees.sstoreRefundGas.v))
+          runState.gasRefund.iaddn(fees.sstoreRefundGas.v)
         } else if (value.length !== 0 && !found.length) {
           subGas(runState, new BN(fees.sstoreSetGas.v))
         } else if (value.length !== 0 && found.length) {
@@ -546,8 +546,8 @@ module.exports = {
         }
 
         if (!value.isZero()) {
-          runState.gasLeft.iadd(new BN(fees.callStipend.v))
-          options.gasLimit.iadd(new BN(fees.callStipend.v))
+          runState.gasLeft.iaddn(fees.callStipend.v)
+          options.gasLimit.iaddn(fees.callStipend.v)
         }
 
         makeCall(runState, options, localOpts, done)
@@ -583,8 +583,8 @@ module.exports = {
     checkOutOfGas(runState, options)
 
     if (!value.isZero()) {
-      runState.gasLeft.iadd(new BN(fees.callStipend.v))
-      options.gasLimit.iadd(new BN(fees.callStipend.v))
+      runState.gasLeft.iaddn(fees.callStipend.v)
+      options.gasLimit.iaddn(fees.callStipend.v)
     }
 
     // load the code
@@ -710,7 +710,6 @@ module.exports = {
     var stateManager = runState.stateManager
     var contract = runState.contract
     var contractAddress = runState.address
-    var zeroBalance = new BN(0)
     selfdestructToAddress = addressToBuffer(selfdestructToAddress)
 
     stateManager.getAccount(selfdestructToAddress, function (err, toAccount) {
@@ -726,7 +725,7 @@ module.exports = {
           return
         }
 
-        if ((new BN(contract.balance)).gt(zeroBalance)) {
+        if ((new BN(contract.balance)).gtn(0)) {
           if (!toAccount.exists || empty) {
             try {
               subGas(runState, new BN(fees.callNewAccountGas.v))
@@ -739,7 +738,7 @@ module.exports = {
 
         // only add to refund if this is the first selfdestruct for the address
         if (!runState.selfdestruct[contractAddress.toString('hex')]) {
-          runState.gasRefund = runState.gasRefund.add(new BN(fees.suicideRefundGas.v))
+          runState.gasRefund = runState.gasRefund.addn(fees.suicideRefundGas.v)
         }
         runState.selfdestruct[contractAddress.toString('hex')] = selfdestructToAddress
         runState.stopped = true
@@ -863,7 +862,7 @@ function memStore (runState, offset, val, valOffset, length, skipSubMem) {
 
   var safeLen = 0
   if (valOffset.addn(length).gtn(val.length)) {
-    if (valOffset.gte(new BN(val.length))) {
+    if (valOffset.gten(val.length)) {
       safeLen = 0
     } else {
       valOffset = valOffset.toNumber()
@@ -910,7 +909,7 @@ function checkCallMemCost (runState, callOptions, localOpts) {
 }
 
 function checkOutOfGas (runState, callOptions) {
-  const gasAllowed = runState.gasLeft.sub(runState.gasLeft.div(new BN(64)))
+  const gasAllowed = runState.gasLeft.sub(runState.gasLeft.divn(64))
   if (callOptions.gasLimit.gt(gasAllowed)) {
     callOptions.gasLimit = gasAllowed
   }
diff --git a/lib/runBlock.js b/lib/runBlock.js
index c6e4df2c4f..37383bdbff 100644
--- a/lib/runBlock.js
+++ b/lib/runBlock.js
@@ -189,8 +189,8 @@ module.exports = function (opts, cb) {
     ommers.forEach(rewardOmmer)
 
     // calculate nibling reward
-    var niblingReward = minerReward.div(new BN(32))
-    var totalNiblingReward = niblingReward.mul(new BN(ommers.length))
+    var niblingReward = minerReward.divn(32)
+    var totalNiblingReward = niblingReward.muln(ommers.length)
     minerAccount = self.stateManager.cache.get(block.header.coinbase)
     // give miner the block reward
     minerAccount.balance = new BN(minerAccount.balance)
@@ -203,9 +203,9 @@ module.exports = function (opts, cb) {
   function rewardOmmer (ommer) {
     // calculate reward
     var heightDiff = new BN(block.header.number).sub(new BN(ommer.number))
-    var reward = ((new BN(8)).sub(heightDiff)).mul(minerReward.div(new BN(8)))
+    var reward = ((new BN(8)).sub(heightDiff)).mul(minerReward.divn(8))
 
-    if (reward.lt(new BN(0))) {
+    if (reward.ltn(0)) {
       reward = new BN(0)
     }