diff --git a/.autover/changes/d0cfdbc8-e15b-49ae-b0b4-ec882dec15f2.json b/.autover/changes/d0cfdbc8-e15b-49ae-b0b4-ec882dec15f2.json
new file mode 100644
index 000000000..807ffaf08
--- /dev/null
+++ b/.autover/changes/d0cfdbc8-e15b-49ae-b0b4-ec882dec15f2.json
@@ -0,0 +1,11 @@
+{
+  "Projects": [
+    {
+      "Name": "Amazon.Lambda.TestTool",
+      "Type": "Patch",
+      "ChangelogMessages": [
+        "Support optional SQS client region in event source test tool"
+      ]
+    }
+  ]
+}
diff --git a/Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Processes/SQSEventSource/SQSEventSourceBackgroundService.cs b/Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Processes/SQSEventSource/SQSEventSourceBackgroundService.cs
index 2125b6f9a..62e214ae8 100644
--- a/Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Processes/SQSEventSource/SQSEventSourceBackgroundService.cs
+++ b/Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Processes/SQSEventSource/SQSEventSourceBackgroundService.cs
@@ -43,7 +43,7 @@ public SQSEventSourceBackgroundService(ILogger<SQSEventSourceProcess> logger, IA
         _lambdaClient = lambdaClient;
     }
 
-    private async Task<string> GetQueueArn(CancellationToken stoppingToken)
+    private async Task<Arn> GetQueueArn(CancellationToken stoppingToken)
     {
         var response = await _sqsClient.GetQueueAttributesAsync(new GetQueueAttributesRequest
         {
@@ -51,7 +51,7 @@ private async Task<string> GetQueueArn(CancellationToken stoppingToken)
             AttributeNames = new List<string> { "QueueArn" }
         }, stoppingToken);
 
-        return response.QueueARN;
+        return Arn.Parse(response.QueueARN);
     }
 
     /// <summary>
@@ -94,7 +94,7 @@ protected override async Task ExecuteAsync(CancellationToken stoppingToken)
 
                 var lambdaPayload = new
                 {
-                    Records = ConvertToLambdaMessages(response.Messages, _sqsClient.Config.RegionEndpoint.SystemName, queueArn)
+                    Records = ConvertToLambdaMessages(response.Messages, queueArn)
                 };
 
                 var invokeRequest = new InvokeRequest
@@ -187,29 +187,27 @@ protected override async Task ExecuteAsync(CancellationToken stoppingToken)
     /// Convert from the SDK's list of messages to the Lambda event's SQS message type.
     /// </summary>
     /// <param name="messages">List of messages using the SDK's .NET type</param>
-    /// <param name="awsRegion">The aws region the messages came from.</param>
     /// <param name="queueArn">The SQS queue arn the messages came from.</param>
     /// <returns>List of messages using the Lambda event's .NET type.</returns>
-    internal static List<SQSEvent.SQSMessage> ConvertToLambdaMessages(List<Message> messages, string awsRegion, string queueArn)
+    internal static List<SQSEvent.SQSMessage> ConvertToLambdaMessages(List<Message> messages, Arn queueArn)
     {
-        return messages.Select(m => ConvertToLambdaMessage(m, awsRegion, queueArn)).ToList();
+        return messages.Select(m => ConvertToLambdaMessage(m, queueArn)).ToList();
     }
 
     /// <summary>
     /// Convert from the SDK's SQS message to the Lambda event's SQS message type.
     /// </summary>
     /// <param name="message">Message using the SDK's .NET type</param>
-    /// <param name="awsRegion">The aws region the message came from.</param>
     /// <param name="queueArn">The SQS queue arn the message came from.</param>
     /// <returns>Messages using the Lambda event's .NET type.</returns>
-    internal static SQSEvent.SQSMessage ConvertToLambdaMessage(Message message, string awsRegion, string queueArn)
+    internal static SQSEvent.SQSMessage ConvertToLambdaMessage(Message message, Arn queueArn)
     {
         var lambdaMessage = new SQSEvent.SQSMessage
         {
-            AwsRegion = awsRegion,
+            AwsRegion = queueArn.Region,
             Body = message.Body,
             EventSource = "aws:sqs",
-            EventSourceArn = queueArn,
+            EventSourceArn = queueArn.ToString(),
             Md5OfBody = message.MD5OfBody,
             Md5OfMessageAttributes = message.MD5OfMessageAttributes,
             MessageId = message.MessageId,
diff --git a/Tools/LambdaTestTool-v2/tests/Amazon.Lambda.TestTool.UnitTests/SQSEventSource/ConvertSDKToLambdaEventTests.cs b/Tools/LambdaTestTool-v2/tests/Amazon.Lambda.TestTool.UnitTests/SQSEventSource/ConvertSDKToLambdaEventTests.cs
index c8722551d..31a08b5ae 100644
--- a/Tools/LambdaTestTool-v2/tests/Amazon.Lambda.TestTool.UnitTests/SQSEventSource/ConvertSDKToLambdaEventTests.cs
+++ b/Tools/LambdaTestTool-v2/tests/Amazon.Lambda.TestTool.UnitTests/SQSEventSource/ConvertSDKToLambdaEventTests.cs
@@ -24,9 +24,10 @@ public void ConvertSDKMessageFull()
             ReceiptHandle = "receiptHandle"
         };
 
-        var eventMessage = SQSEventSourceBackgroundService.ConvertToLambdaMessage(sdkMessage, "us-west-2", "queueArn");
+        var queueArn = Arn.Parse("arn:aws:sqs:us-west-2:123456789012:queueName");
+        var eventMessage = SQSEventSourceBackgroundService.ConvertToLambdaMessage(sdkMessage, queueArn);
         Assert.Equal("us-west-2", eventMessage.AwsRegion);
-        Assert.Equal("queueArn", eventMessage.EventSourceArn);
+        Assert.Equal("arn:aws:sqs:us-west-2:123456789012:queueName", eventMessage.EventSourceArn);
         Assert.Equal("aws:sqs", eventMessage.EventSource);
 
         Assert.Equal(sdkMessage.Attributes, eventMessage.Attributes);
@@ -61,9 +62,10 @@ public void ConvertSDKMessageWithNullCollections()
             ReceiptHandle = "receiptHandle"
         };
 
-        var eventMessage = SQSEventSourceBackgroundService.ConvertToLambdaMessage(sdkMessage, "us-west-2", "queueArn");
+        var queueArn = Arn.Parse("arn:aws:sqs:us-west-2:123456789012:queueName");
+        var eventMessage = SQSEventSourceBackgroundService.ConvertToLambdaMessage(sdkMessage, queueArn);
         Assert.Equal("us-west-2", eventMessage.AwsRegion);
-        Assert.Equal("queueArn", eventMessage.EventSourceArn);
+        Assert.Equal("arn:aws:sqs:us-west-2:123456789012:queueName", eventMessage.EventSourceArn);
         Assert.Equal("aws:sqs", eventMessage.EventSource);
 
         Assert.Equal("theBody", eventMessage.Body);