diff --git a/test/fee.t.sol b/test/fee.t.sol
index 564f229f..b4b94289 100644
--- a/test/fee.t.sol
+++ b/test/fee.t.sol
@@ -17,23 +17,46 @@ contract FeeTest is PacketSenderTest {
 
     PacketFee[] packetFees;
 
+    modifier useFeeTestCases() {
+        // initialize an array of PacketFee with different values
+        packetFees.push(PacketFee(0, 0, 0));
+        packetFees.push(PacketFee(1, 0, 0));
+        packetFees.push(PacketFee(0, 1, 0));
+        packetFees.push(PacketFee(0, 0, 1));
+        packetFees.push(PacketFee(1, 1, 1));
+        packetFees.push(PacketFee(1, 2, 3));
+        packetFees.push(PacketFee(2, 2, 1));
+        packetFees.push(PacketFee(1, 1, 2));
+        packetFees.push(PacketFee(1, 2, 2));
+        packetFees.push(PacketFee(3, 2, 1));
+
+        for (uint i = 0; i < packetFees.length; i++) {
+            fee = packetFees[i];
+            _;
+        }
+    }
+
     // pay extra packet fee after packet creation
-    function test_payPacketFeeAsync() public {
-        PacketFee memory accu = mergeFees(fee, fee);
+    function test_payPacketFeeAsync() public useFeeTestCases {
+        // merge fees to calculate expected packet fee
+        PacketFee memory extraFee = PacketFee(1, 2, 3);
+        PacketFee memory expectedFee = mergeFees(fee, extraFee);
+
         for (uint64 index = 0; index < 3; index++) {
-            uint64 packetSeq = index + 1;
+            // create packet and pay escrow fee
+            sendPacket();
 
-            mars.greet{value: Ibc.calcEscrowFee(fee)}(
-                IbcDispatcher(dispatcher),
-                payloadStr,
+            // pay packet fee asynchronously
+            dispatcher.payPacketFeeAsync{value: Ibc.calcEscrowFee(extraFee)}(
+                address(mars),
                 channelId,
-                maxTimeout,
-                fee
+                sentPacket.sequence,
+                extraFee
             );
-            dispatcher.payPacketFeeAsync{value: Ibc.calcEscrowFee(fee)}(address(mars), channelId, packetSeq, fee);
 
-            PacketFee memory packetFee = dispatcher.getTotalPacketFees(address(mars), channelId, packetSeq);
-            assertEq(keccak256(abi.encode(packetFee)), keccak256(abi.encode(accu)));
+            // check that the total packet fee is correct
+            PacketFee memory actualFee = dispatcher.getTotalPacketFees(address(mars), channelId, sentPacket.sequence);
+            assertEq(keccak256(abi.encode(actualFee)), keccak256(abi.encode(expectedFee)), 'Packet fee is incorrect');
         }
     }
 
@@ -49,25 +72,6 @@ contract FeeTest is PacketSenderTest {
         );
     }
 
-    modifier useFeeTestCases() {
-        // initialize an array of PacketFee with different values
-        packetFees.push(PacketFee(0, 0, 0));
-        packetFees.push(PacketFee(1, 0, 0));
-        packetFees.push(PacketFee(0, 1, 0));
-        packetFees.push(PacketFee(0, 0, 1));
-        packetFees.push(PacketFee(1, 1, 1));
-        packetFees.push(PacketFee(1, 2, 3));
-        packetFees.push(PacketFee(2, 2, 1));
-        packetFees.push(PacketFee(1, 1, 2));
-        packetFees.push(PacketFee(1, 2, 2));
-        packetFees.push(PacketFee(3, 2, 1));
-
-        for (uint i = 0; i < packetFees.length; i++) {
-            fee = packetFees[i];
-            _;
-        }
-    }
-
     // claim ack fee on receving ack
     function test_ack_fee() public useFeeTestCases {
         // save balances of forward and reverse relayer payees; assert balances changes after ack
@@ -99,21 +103,22 @@ contract FeeTest is PacketSenderTest {
     }
 
     // claim timeout fee on receving timeout
-    function test_timeout_fee() public {
-        assertEq(address(forwardRelayerPayee).balance, 0);
-        assertEq(address(reverseRelayerPayee).balance, 0);
+    function test_timeout_fee() public useFeeTestCases {
+        uint balanceReverseRelayer1 = address(reverseRelayerPayee).balance;
+        address refundPayee = address(mars);
+        uint balanceRefund1 = refundPayee.balance;
 
+        vm.startPrank(relayer);
         sendPacket();
 
-        uint balance1 = address(mars).balance;
-
         vm.startPrank(reverseRelayerPayee, reverseRelayerPayee);
         dispatcher.timeout(IbcReceiver(mars), sentPacket, validProof);
 
-        assertEq(address(reverseRelayerPayee).balance, fee.timeoutFee);
+        assertEq(address(reverseRelayerPayee).balance, fee.timeoutFee + balanceReverseRelayer1);
+        // no forward relayer is invovled in timeout case
         assertEq(address(forwardRelayerPayee).balance, 0);
+        assertEq(refundPayee.balance, Ibc.timeoutRefundAmount(fee) + balanceRefund1);
         assertEq(escrow.balance, 0);
-        assertEq(address(mars).balance, balance1 + Ibc.timeoutRefundAmount(fee));
 
         // cannot claim timeout fee twice
         vm.expectRevert();