diff --git a/src/main/resources/templates/client-code/api-models.kt.hbs b/src/main/resources/templates/client-code/api-models.kt.hbs
index 86c54001..421cb7fd 100644
--- a/src/main/resources/templates/client-code/api-models.kt.hbs
+++ b/src/main/resources/templates/client-code/api-models.kt.hbs
@@ -12,7 +12,7 @@ data class ApiResponse<T>(val statusCode: Int, val headers: Headers, val data: T
 /**
  * API non-2xx failure responses returned by API call.
  */
-open class ApiException(override val message: String) : Exception(message)
+open class ApiException(override val message: String) : RuntimeException(message)
 
 /**
  * API 4xx failure responses returned by API call.
diff --git a/src/test/resources/examples/okHttpClient/client/ApiModels.kt b/src/test/resources/examples/okHttpClient/client/ApiModels.kt
index 861c5071..a7a9ae30 100644
--- a/src/test/resources/examples/okHttpClient/client/ApiModels.kt
+++ b/src/test/resources/examples/okHttpClient/client/ApiModels.kt
@@ -12,7 +12,7 @@ data class ApiResponse<T>(val statusCode: Int, val headers: Headers, val data: T
 /**
  * API non-2xx failure responses returned by API call.
  */
-open class ApiException(override val message: String) : Exception(message)
+open class ApiException(override val message: String) : RuntimeException(message)
 
 /**
  * API 4xx failure responses returned by API call.
diff --git a/src/test/resources/examples/okHttpClientMultiMediaType/client/ApiModels.kt b/src/test/resources/examples/okHttpClientMultiMediaType/client/ApiModels.kt
index 3358c7d3..a4d96993 100644
--- a/src/test/resources/examples/okHttpClientMultiMediaType/client/ApiModels.kt
+++ b/src/test/resources/examples/okHttpClientMultiMediaType/client/ApiModels.kt
@@ -12,7 +12,7 @@ data class ApiResponse<T>(val statusCode: Int, val headers: Headers, val data: T
 /**
  * API non-2xx failure responses returned by API call.
  */
-open class ApiException(override val message: String) : Exception(message)
+open class ApiException(override val message: String) : RuntimeException(message)
 
 /**
  * API 4xx failure responses returned by API call.
diff --git a/src/test/resources/examples/okHttpClientPostWithoutRequestBody/client/ApiModels.kt b/src/test/resources/examples/okHttpClientPostWithoutRequestBody/client/ApiModels.kt
index ca59e3c3..df87b810 100644
--- a/src/test/resources/examples/okHttpClientPostWithoutRequestBody/client/ApiModels.kt
+++ b/src/test/resources/examples/okHttpClientPostWithoutRequestBody/client/ApiModels.kt
@@ -12,7 +12,7 @@ data class ApiResponse<T>(val statusCode: Int, val headers: Headers, val data: T
 /**
  * API non-2xx failure responses returned by API call.
  */
-open class ApiException(override val message: String) : Exception(message)
+open class ApiException(override val message: String) : RuntimeException(message)
 
 /**
  * API 4xx failure responses returned by API call.
diff --git a/src/test/resources/examples/parameterNameClash/client/ApiModels.kt b/src/test/resources/examples/parameterNameClash/client/ApiModels.kt
index e7de8131..d7f6bf62 100644
--- a/src/test/resources/examples/parameterNameClash/client/ApiModels.kt
+++ b/src/test/resources/examples/parameterNameClash/client/ApiModels.kt
@@ -12,7 +12,7 @@ data class ApiResponse<T>(val statusCode: Int, val headers: Headers, val data: T
 /**
  * API non-2xx failure responses returned by API call.
  */
-open class ApiException(override val message: String) : Exception(message)
+open class ApiException(override val message: String) : RuntimeException(message)
 
 /**
  * API 4xx failure responses returned by API call.
diff --git a/src/test/resources/examples/pathLevelParameters/client/ApiModels.kt b/src/test/resources/examples/pathLevelParameters/client/ApiModels.kt
index 8050e32c..0d3871e3 100644
--- a/src/test/resources/examples/pathLevelParameters/client/ApiModels.kt
+++ b/src/test/resources/examples/pathLevelParameters/client/ApiModels.kt
@@ -12,7 +12,7 @@ data class ApiResponse<T>(val statusCode: Int, val headers: Headers, val data: T
 /**
  * API non-2xx failure responses returned by API call.
  */
-open class ApiException(override val message: String) : Exception(message)
+open class ApiException(override val message: String) : RuntimeException(message)
 
 /**
  * API 4xx failure responses returned by API call.