diff --git a/contracts/exchange/contracts/src/MixinExchangeCore.sol b/contracts/exchange/contracts/src/MixinExchangeCore.sol
index 202538cbdf..ee32be26b8 100644
--- a/contracts/exchange/contracts/src/MixinExchangeCore.sol
+++ b/contracts/exchange/contracts/src/MixinExchangeCore.sol
@@ -61,8 +61,7 @@ contract MixinExchangeCore is
     function cancelOrdersUpTo(uint256 targetOrderEpoch)
         external
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
     {
         address makerAddress = _getCurrentContextAddress();
         // If this function is called via `executeTransaction`, we only update the orderEpoch for the makerAddress/msg.sender combination.
@@ -103,8 +102,7 @@ contract MixinExchangeCore is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.FillResults memory fillResults)
     {
         fillResults = _fillOrder(
@@ -120,8 +118,7 @@ contract MixinExchangeCore is
     function cancelOrder(LibOrder.Order memory order)
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
     {
         _cancelOrder(order);
     }
diff --git a/contracts/exchange/contracts/src/MixinMatchOrders.sol b/contracts/exchange/contracts/src/MixinMatchOrders.sol
index 69c914298d..3b5b251b04 100644
--- a/contracts/exchange/contracts/src/MixinMatchOrders.sol
+++ b/contracts/exchange/contracts/src/MixinMatchOrders.sol
@@ -51,8 +51,7 @@ contract MixinMatchOrders is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.BatchMatchedFillResults memory batchMatchedFillResults)
     {
         return _batchMatchOrders(
@@ -81,8 +80,7 @@ contract MixinMatchOrders is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.BatchMatchedFillResults memory batchMatchedFillResults)
     {
         return _batchMatchOrders(
@@ -111,8 +109,7 @@ contract MixinMatchOrders is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.MatchedFillResults memory matchedFillResults)
     {
         return _matchOrders(
@@ -141,8 +138,7 @@ contract MixinMatchOrders is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.MatchedFillResults memory matchedFillResults)
     {
         return _matchOrders(
diff --git a/contracts/exchange/contracts/src/MixinSignatureValidator.sol b/contracts/exchange/contracts/src/MixinSignatureValidator.sol
index f961f1aedf..f0387fded0 100644
--- a/contracts/exchange/contracts/src/MixinSignatureValidator.sol
+++ b/contracts/exchange/contracts/src/MixinSignatureValidator.sol
@@ -22,7 +22,6 @@ pragma experimental ABIEncoderV2;
 import "@0x/contracts-utils/contracts/src/LibBytes.sol";
 import "@0x/contracts-utils/contracts/src/LibEIP1271.sol";
 import "@0x/contracts-utils/contracts/src/LibRichErrors.sol";
-import "@0x/contracts-utils/contracts/src/ReentrancyGuard.sol";
 import "@0x/contracts-exchange-libs/contracts/src/LibOrder.sol";
 import "@0x/contracts-exchange-libs/contracts/src/LibZeroExTransaction.sol";
 import "@0x/contracts-exchange-libs/contracts/src/LibEIP712ExchangeDomain.sol";
@@ -35,7 +34,6 @@ import "./MixinTransactions.sol";
 
 
 contract MixinSignatureValidator is
-    ReentrancyGuard,
     LibEIP712ExchangeDomain,
     LibEIP1271,
     ISignatureValidator,
@@ -61,8 +59,7 @@ contract MixinSignatureValidator is
     function preSign(bytes32 hash)
         external
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
     {
         address signerAddress = _getCurrentContextAddress();
         preSigned[hash][signerAddress] = true;
@@ -78,8 +75,7 @@ contract MixinSignatureValidator is
     )
         external
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
     {
         address signerAddress = _getCurrentContextAddress();
         allowedValidators[signerAddress][validatorAddress] = approval;
@@ -465,7 +461,7 @@ contract MixinSignatureValidator is
         return signatureType;
     }
 
-    /// @dev ABI encodes an order and hash with a selector to be passed into 
+    /// @dev ABI encodes an order and hash with a selector to be passed into
     ///      an EIP1271 compliant `isValidSignature` function.
     function _encodeEIP1271OrderWithHash(
         LibOrder.Order memory order,
@@ -482,7 +478,7 @@ contract MixinSignatureValidator is
         );
     }
 
-    /// @dev ABI encodes a transaction and hash with a selector to be passed into 
+    /// @dev ABI encodes a transaction and hash with a selector to be passed into
     ///      an EIP1271 compliant `isValidSignature` function.
     function _encodeEIP1271TransactionWithHash(
         LibZeroExTransaction.ZeroExTransaction memory transaction,
diff --git a/contracts/exchange/contracts/src/MixinWrapperFunctions.sol b/contracts/exchange/contracts/src/MixinWrapperFunctions.sol
index 2bd0792138..f01e9c084f 100644
--- a/contracts/exchange/contracts/src/MixinWrapperFunctions.sol
+++ b/contracts/exchange/contracts/src/MixinWrapperFunctions.sol
@@ -47,8 +47,7 @@ contract MixinWrapperFunctions is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.FillResults memory fillResults)
     {
         fillResults = _fillOrKillOrder(
@@ -71,8 +70,7 @@ contract MixinWrapperFunctions is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.FillResults[] memory fillResults)
     {
         uint256 ordersLength = orders.length;
@@ -99,8 +97,7 @@ contract MixinWrapperFunctions is
     )
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
         returns (LibFillResults.FillResults[] memory fillResults)
     {
         uint256 ordersLength = orders.length;
@@ -287,8 +284,7 @@ contract MixinWrapperFunctions is
     function batchCancelOrders(LibOrder.Order[] memory orders)
         public
         payable
-        nonReentrant
-        refundFinalBalance
+        refundFinalBalanceNoReentry
     {
         uint256 ordersLength = orders.length;
         for (uint256 i = 0; i != ordersLength; i++) {
diff --git a/contracts/utils/contracts/src/Refundable.sol b/contracts/utils/contracts/src/Refundable.sol
index 42293d9bac..55d32b492b 100644
--- a/contracts/utils/contracts/src/Refundable.sol
+++ b/contracts/utils/contracts/src/Refundable.sol
@@ -18,8 +18,12 @@
 
 pragma solidity ^0.5.9;
 
+import "./ReentrancyGuard.sol";
 
-contract Refundable {
+
+contract Refundable is
+    ReentrancyGuard
+{
 
     // This bool is used by the refund modifier to allow for lazily evaluated refunds.
     bool internal _shouldNotRefund;
@@ -29,6 +33,13 @@ contract Refundable {
         _refundNonZeroBalanceIfEnabled();
     }
 
+    modifier refundFinalBalanceNoReentry {
+        _lockMutexOrThrowIfAlreadyLocked();
+        _;
+        _refundNonZeroBalanceIfEnabled();
+        _unlockMutex();
+    }
+
     modifier disableRefundUntilEnd {
         if (_areRefundsDisabled()) {
             _;