diff --git a/.changelog/smoketestcodegen.md b/.changelog/smoketestcodegen.md
new file mode 100644
index 0000000000..3a52c93979
--- /dev/null
+++ b/.changelog/smoketestcodegen.md
@@ -0,0 +1,12 @@
+---
+applies_to:
+  - aws-sdk-rust
+authors:
+  - landonxjames
+references: [smithy-rs#3836]
+breaking: false
+new_feature: false
+bug_fix: true
+---
+
+Update Smoketest codegeneration to be endpoint built-in aware.
diff --git a/aws/sdk-codegen/src/main/kotlin/software/amazon/smithy/rustsdk/SmokeTestsDecorator.kt b/aws/sdk-codegen/src/main/kotlin/software/amazon/smithy/rustsdk/SmokeTestsDecorator.kt
index 3051ec0cf6..7166c67073 100644
--- a/aws/sdk-codegen/src/main/kotlin/software/amazon/smithy/rustsdk/SmokeTestsDecorator.kt
+++ b/aws/sdk-codegen/src/main/kotlin/software/amazon/smithy/rustsdk/SmokeTestsDecorator.kt
@@ -11,8 +11,10 @@ import software.amazon.smithy.model.node.ObjectNode
 import software.amazon.smithy.model.shapes.MemberShape
 import software.amazon.smithy.model.shapes.OperationShape
 import software.amazon.smithy.model.shapes.StructureShape
+import software.amazon.smithy.rulesengine.language.syntax.parameters.Parameters
 import software.amazon.smithy.rust.codegen.client.smithy.ClientCodegenContext
 import software.amazon.smithy.rust.codegen.client.smithy.customize.ClientCodegenDecorator
+import software.amazon.smithy.rust.codegen.client.smithy.endpoint.EndpointRulesetIndex
 import software.amazon.smithy.rust.codegen.client.smithy.generators.client.FluentClientGenerator
 import software.amazon.smithy.rust.codegen.core.rustlang.Attribute
 import software.amazon.smithy.rust.codegen.core.rustlang.Attribute.Companion.cfg
@@ -42,6 +44,7 @@ import software.amazon.smithy.smoketests.traits.SmokeTestCase
 import software.amazon.smithy.smoketests.traits.SmokeTestsTrait
 import java.util.Optional
 import java.util.logging.Logger
+import kotlin.jvm.optionals.getOrElse
 
 class SmokeTestsDecorator : ClientCodegenDecorator {
     override val name: String = "SmokeTests"
@@ -134,7 +137,7 @@ fun renderPrologue(
         they are disabled by default. To enable them, run the tests with
 
         ```sh
-        RUSTFLAGS="--cfg smoketests" cargo test.
+        RUSTFLAGS="--cfg smoketests" cargo test
         ```
         """,
     )
@@ -167,6 +170,17 @@ class SmokeTestsInstantiator(
     ) {
     private val model = codegenContext.model
     private val symbolProvider = codegenContext.symbolProvider
+    private val builtInParamNames: List<String> by lazy {
+        val index = EndpointRulesetIndex.of(codegenContext.model)
+        val rulesOrNull = index.endpointRulesForService(codegenContext.serviceShape)
+        val builtInParams: Parameters = (rulesOrNull?.parameters ?: Parameters.builder().build())
+        val temp: MutableList<String> = mutableListOf()
+        builtInParams.forEach { temp.add(it.builtIn.getOrElse { "" }) }
+        temp
+    }
+    private val fipsName = "AWS::UseFIPS"
+    private val dualStackName = "AWS::UseDualStack"
+    private val rc = codegenContext.runtimeConfig
 
     fun render(
         writer: RustWriter,
@@ -191,9 +205,18 @@ class SmokeTestsInstantiator(
 
         val vendorParams = AwsSmokeTestModel.getAwsVendorParams(testCase)
         vendorParams.orNull()?.let { params ->
-            rust(".region(config::Region::new(${params.region.dq()}))")
-            rust(".use_dual_stack(${params.useDualstack()})")
-            rust(".use_fips(${params.useFips()})")
+            rustTemplate(
+                ".region(#{Region}::new(${params.region.dq()}))",
+                "Region" to AwsRuntimeType.awsTypes(rc).resolve("region::Region"),
+            )
+
+            if (builtInParamNames.contains(dualStackName)) {
+                rust(".use_dual_stack(${params.useDualstack()})")
+            }
+            if (builtInParamNames.contains(fipsName)) {
+                rust(".use_fips(${params.useFips()})")
+            }
+
             params.uri.orNull()?.let { rust(".endpoint_url($it)") }
         }