diff --git a/contracts/src/RIP7755Inbox.sol b/contracts/src/RIP7755Inbox.sol
index 580242c..cbd0c37 100644
--- a/contracts/src/RIP7755Inbox.sol
+++ b/contracts/src/RIP7755Inbox.sol
@@ -28,7 +28,7 @@ contract RIP7755Inbox {
         /// @dev Block timestamp when fulfilled
         uint96 timestamp;
         /// @dev Msg.sender of fulfillment call
-        address filler;
+        address fulfiller;
     }
 
     // Main storage location used as the base for the fulfillmentInfo mapping following EIP-7201. (keccak256("RIP-7755"))
@@ -87,7 +87,7 @@ contract RIP7755Inbox {
             revert CallAlreadyFulfilled();
         }
 
-        _setFulfillmentInfo(requestHash, FulfillmentInfo({timestamp: uint96(block.timestamp), filler: fulfiller}));
+        _setFulfillmentInfo(requestHash, FulfillmentInfo({timestamp: uint96(block.timestamp), fulfiller: fulfiller}));
 
         _sendCallsAndValidateMsgValue(request);
 
diff --git a/contracts/src/RIP7755Outbox.sol b/contracts/src/RIP7755Outbox.sol
index e9fde2b..70d7372 100644
--- a/contracts/src/RIP7755Outbox.sol
+++ b/contracts/src/RIP7755Outbox.sol
@@ -50,6 +50,11 @@ abstract contract RIP7755Outbox {
     /// @param request The requested cross chain call
     event CrossChainCallRequested(bytes32 indexed requestHash, CrossChainRequest request);
 
+    /// @notice Event emitted when a cross chain call is successfully completed
+    /// @param requestHash The keccak256 hash of a `CrossChainRequest`
+    /// @param submitter The address of the fulfiller that successfully completed the cross chain call
+    event CrossChainCallCompleted(bytes32 indexed requestHash, address submitter);
+
     /// @notice Event emitted when an expired cross chain call request is canceled
     /// @param requestHash The keccak256 hash of a `CrossChainRequest`
     event CrossChainCallCanceled(bytes32 indexed requestHash);
@@ -129,6 +134,8 @@ abstract contract RIP7755Outbox {
         _requestStatus[requestHash] = CrossChainCallStatus.Completed;
 
         _sendReward(request, payTo);
+
+        emit CrossChainCallCompleted(requestHash, msg.sender);
     }
 
     /// @notice Cancels a pending request that has expired
@@ -249,7 +256,7 @@ abstract contract RIP7755Outbox {
         returns (RIP7755Inbox.FulfillmentInfo memory)
     {
         RIP7755Inbox.FulfillmentInfo memory fulfillmentInfo;
-        fulfillmentInfo.filler = address(uint160((uint256(inboxContractStorageValue) >> 96) & type(uint160).max));
+        fulfillmentInfo.fulfiller = address(uint160((uint256(inboxContractStorageValue) >> 96) & type(uint160).max));
         fulfillmentInfo.timestamp = uint96(uint256(inboxContractStorageValue));
         return fulfillmentInfo;
     }
diff --git a/contracts/test/HashiProver.t.sol b/contracts/test/HashiProver.t.sol
index 21f4fef..f470c8a 100644
--- a/contracts/test/HashiProver.t.sol
+++ b/contracts/test/HashiProver.t.sol
@@ -145,10 +145,6 @@ contract HashiProverTest is Test {
         });
     }
 
-    function _initFulfillmentInfo() private view returns (RIP7755Inbox.FulfillmentInfo memory) {
-        return RIP7755Inbox.FulfillmentInfo({timestamp: 1730125190, filler: FILLER});
-    }
-
     function _deriveStorageKey(CrossChainRequest memory request) private pure returns (bytes memory) {
         bytes32 requestHash = keccak256(abi.encode(request));
         return abi.encode(keccak256(abi.encodePacked(requestHash, _VERIFIER_STORAGE_LOCATION)));
diff --git a/contracts/test/RIP7755Inbox.t.sol b/contracts/test/RIP7755Inbox.t.sol
index ba564e4..8f4f205 100644
--- a/contracts/test/RIP7755Inbox.t.sol
+++ b/contracts/test/RIP7755Inbox.t.sol
@@ -63,7 +63,7 @@ contract RIP7755InboxTest is Test {
         bytes32 requestHash = inbox.hashRequest(request);
         RIP7755Inbox.FulfillmentInfo memory info = inbox.getFulfillmentInfo(requestHash);
 
-        assertEq(info.filler, FULFILLER);
+        assertEq(info.fulfiller, FULFILLER);
         assertEq(info.timestamp, block.timestamp);
     }
 
@@ -152,7 +152,7 @@ contract RIP7755InboxTest is Test {
         bytes32 requestHash = inbox.hashRequest(request);
         RIP7755Inbox.FulfillmentInfo memory info = inbox.getFulfillmentInfo(requestHash);
 
-        assertEq(info.filler, FULFILLER);
+        assertEq(info.fulfiller, FULFILLER);
         assertEq(info.timestamp, block.timestamp);
     }
 
@@ -167,7 +167,7 @@ contract RIP7755InboxTest is Test {
         bytes32 requestHash = inbox.hashRequest(request);
         RIP7755Inbox.FulfillmentInfo memory info = inbox.getFulfillmentInfo(requestHash);
 
-        assertEq(info.filler, FULFILLER);
+        assertEq(info.fulfiller, FULFILLER);
         assertEq(info.timestamp, block.timestamp);
     }
 
diff --git a/contracts/test/RIP7755Outbox.t.sol b/contracts/test/RIP7755Outbox.t.sol
index 925dea7..3e9943b 100644
--- a/contracts/test/RIP7755Outbox.t.sol
+++ b/contracts/test/RIP7755Outbox.t.sol
@@ -23,6 +23,7 @@ contract RIP7755OutboxTest is Test {
     bytes32 private constant _NATIVE_ASSET = 0x000000000000000000000000eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee;
 
     event CrossChainCallRequested(bytes32 indexed requestHash, CrossChainRequest request);
+    event CrossChainCallCompleted(bytes32 indexed requestHash, address submitter);
     event CrossChainCallCanceled(bytes32 indexed callHash);
 
     function setUp() public {
@@ -218,6 +219,20 @@ contract RIP7755OutboxTest is Test {
         outbox.claimReward(request, storageProofData, FILLER);
     }
 
+    function test_claimReward_emitsEvent(uint256 rewardAmount)
+        external
+        fundAlice(rewardAmount)
+    {
+        CrossChainRequest memory request = _submitRequest(rewardAmount);
+        bytes memory storageProofData = abi.encode(true);
+        bytes32 requestHash = outbox.hashRequest(request);
+
+        vm.prank(FILLER);
+        vm.expectEmit(true, false, false, true);
+        emit CrossChainCallCompleted(requestHash, FILLER);
+        outbox.claimReward(request, storageProofData, FILLER);
+    }
+
     function test_claimReward_storesCompletedStatus_pendingState(uint256 rewardAmount)
         external
         fundAlice(rewardAmount)