diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift5ClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift5ClientCodegen.java
index d4c680030fe0..1dbbb7ff7078 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift5ClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift5ClientCodegen.java
@@ -588,7 +588,7 @@ public class Swift5ClientCodegen extends DefaultCodegen implements CodegenConfig
         supportingFiles.add(new SupportingFile("OpenISO8601DateFormatter.mustache",
                 sourceFolder,
                 "OpenISO8601DateFormatter.swift"));
-        if (additionalProperties.containsKey(USE_CUSTOM_DATE_WITHOUT_TIME)) {
+        if (useCustomDateWithoutTime) {
             supportingFiles.add(new SupportingFile("OpenAPIDateWithoutTime.mustache",
                 sourceFolder,
                 "OpenAPIDateWithoutTime.swift"));