diff --git a/src/aws-cpp-sdk-core/include/aws/core/client/ClientConfiguration.h b/src/aws-cpp-sdk-core/include/aws/core/client/ClientConfiguration.h
index 9799edfa69a..77abb91d926 100644
--- a/src/aws-cpp-sdk-core/include/aws/core/client/ClientConfiguration.h
+++ b/src/aws-cpp-sdk-core/include/aws/core/client/ClientConfiguration.h
@@ -398,6 +398,12 @@ namespace Aws
              */
             bool enableHttpClientTrace = false;
 
+            /**
+             * Serialize XML request payloads without pretty-printing whitespace (indentation and newlines),
+             * producing a smaller payload. Defaults to false to preserve existing serialization behavior.
+             */
+            bool compactXmlSerialization = false;
+
             /**
              * profileName in config file that will be used by this object to resolve more configurations.
              */
diff --git a/src/aws-cpp-sdk-core/include/aws/core/utils/xml/XmlSerializer.h b/src/aws-cpp-sdk-core/include/aws/core/utils/xml/XmlSerializer.h
index 8d410479976..0dd2739820d 100644
--- a/src/aws-cpp-sdk-core/include/aws/core/utils/xml/XmlSerializer.h
+++ b/src/aws-cpp-sdk-core/include/aws/core/utils/xml/XmlSerializer.h
@@ -175,6 +175,11 @@ namespace Aws
                  * Convert entire document to string. Use this if you for example, want to save the document to a file.
                  */
                 Aws::String ConvertToString() const;
+                /**
+                 * Convert entire document to string. When compact is true, the output omits pretty-printing
+                 * whitespace (indentation and newlines), producing a smaller payload.
+                 */
+                Aws::String ConvertToString(bool compact) const;
                 /**
                  * Returns true if the call to CreateFromXml* was successful, otherwise false.
                  * if this returns false, you can call GetErrorMessage() to see details.
diff --git a/src/aws-cpp-sdk-core/source/utils/xml/XmlSerializer.cpp b/src/aws-cpp-sdk-core/source/utils/xml/XmlSerializer.cpp
index 3b2441f0dc3..cc30e221be0 100644
--- a/src/aws-cpp-sdk-core/source/utils/xml/XmlSerializer.cpp
+++ b/src/aws-cpp-sdk-core/source/utils/xml/XmlSerializer.cpp
@@ -274,10 +274,15 @@ Aws::String XmlDocument::GetErrorMessage() const
 }
 
 Aws::String XmlDocument::ConvertToString() const
+{
+    return ConvertToString(false);
+}
+
+Aws::String XmlDocument::ConvertToString(bool compact) const
 {
     if (!m_doc) return "";
 
-    Aws::External::tinyxml2::XMLPrinter printer;
+    Aws::External::tinyxml2::XMLPrinter printer(nullptr, compact);
     printer.PushHeader(false, true);
     m_doc->Accept(&printer);
 
diff --git a/tests/aws-cpp-sdk-core-tests/utils/xml/XmlSerializerTest.cpp b/tests/aws-cpp-sdk-core-tests/utils/xml/XmlSerializerTest.cpp
index a8f80783811..1a37d34078e 100644
--- a/tests/aws-cpp-sdk-core-tests/utils/xml/XmlSerializerTest.cpp
+++ b/tests/aws-cpp-sdk-core-tests/utils/xml/XmlSerializerTest.cpp
@@ -77,6 +77,31 @@ TEST_F(XmlSerializerTest, TestXmlSerialize)
     ASSERT_TRUE(doc.GetErrorMessage().empty());
 }
 
+TEST_F(XmlSerializerTest, TestXmlSerializeCompact)
+{
+    XmlDocument doc = XmlDocument::CreateWithRootNode("ToDo");
+    XmlNode rootElement = doc.GetRootElement();
+    XmlNode item1 = rootElement.CreateChildElement("Item");
+    item1.SetAttributeValue("priority", "1");
+    item1.SetText("Go to the <bold>Toy store!</bold>");
+    XmlNode item2 = rootElement.CreateChildElement("Item");
+    item2.SetAttributeValue("priority", "2");
+    item2.SetText("Do bills");
+
+    Aws::String serializedXml = doc.ConvertToString(true);
+
+    Aws::String toCompare = "<?xml version=\"1.0\"?>"
+        "<ToDo>"
+        "<Item priority=\"1\">Go to the &lt;bold&gt;Toy store!&lt;/bold&gt;</Item>"
+        "<Item priority=\"2\">Do bills</Item>"
+        "</ToDo>";
+    ASSERT_EQ(toCompare, serializedXml);
+    ASSERT_TRUE(doc.GetErrorMessage().empty());
+
+    // The no-arg overload preserves the pretty-printed default.
+    ASSERT_EQ(doc.ConvertToString(false), doc.ConvertToString());
+}
+
 TEST_F(XmlSerializerTest, TestXmlSerializeNewlines)
 {
     XmlDocument doc = XmlDocument::CreateWithRootNode("Newlines");