diff --git a/modules/openapi-generator-cli/src/main/java/org/openapitools/codegen/cmd/Meta.java b/modules/openapi-generator-cli/src/main/java/org/openapitools/codegen/cmd/Meta.java
index e16b281d6d3..aad40007dee 100644
--- a/modules/openapi-generator-cli/src/main/java/org/openapitools/codegen/cmd/Meta.java
+++ b/modules/openapi-generator-cli/src/main/java/org/openapitools/codegen/cmd/Meta.java
@@ -36,6 +36,7 @@ import org.slf4j.LoggerFactory;
 import java.io.File;
 import java.io.IOException;
 import java.io.Reader;
+import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.Map;
 
@@ -159,7 +160,7 @@ public class Meta implements Runnable {
                         LOGGER.info("copying file to {}", outputFile.getAbsolutePath());
                     }
 
-                    FileUtils.writeStringToFile(outputFile, formatted);
+                    FileUtils.writeStringToFile(outputFile, formatted, StandardCharsets.UTF_8);
                     return outputFile;
 
                 } catch (IOException e) {
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/OpenAPIGenerator.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/OpenAPIGenerator.java
index 00258016667..453ddb44bac 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/OpenAPIGenerator.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/OpenAPIGenerator.java
@@ -29,6 +29,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.File;
+import java.nio.charset.StandardCharsets;
 import java.util.EnumSet;
 
 public class OpenAPIGenerator extends DefaultCodegen implements CodegenConfig {
@@ -75,7 +76,7 @@ public class OpenAPIGenerator extends DefaultCodegen implements CodegenConfig {
 
         try {
             String outputFile = outputFolder + File.separator + "openapi.json";
-            FileUtils.writeStringToFile(new File(outputFile), jsonOpenAPI);
+            FileUtils.writeStringToFile(new File(outputFile), jsonOpenAPI, StandardCharsets.UTF_8);
             LOGGER.info("wrote file to " + outputFile);
         } catch (Exception e) {
             LOGGER.error(e.getMessage(), e);
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaGatlingCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaGatlingCodegen.java
index 6cb78122284..06c504bf517 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaGatlingCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaGatlingCodegen.java
@@ -35,6 +35,7 @@ import org.slf4j.LoggerFactory;
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.util.*;
 
 public class ScalaGatlingCodegen extends AbstractScalaCodegen implements CodegenConfig {
@@ -312,7 +313,11 @@ public class ScalaGatlingCodegen extends AbstractScalaCodegen implements Codegen
                             operation.setVendorExtension("x-gatling-body-feeder", operation.getOperationId() + "BodyFeeder");
                             operation.setVendorExtension("x-gatling-body-feeder-params", StringUtils.join(sessionBodyVars, ","));
                             try {
-                                FileUtils.writeStringToFile(new File(outputFolder + File.separator + dataFolder + File.separator + operation.getOperationId() + "-" + "bodyParams.csv"), StringUtils.join(bodyFeederParams, ","));
+                                FileUtils.writeStringToFile(
+                                    new File(outputFolder + File.separator + dataFolder + File.separator + operation.getOperationId() + "-" + "bodyParams.csv"),
+                                    StringUtils.join(bodyFeederParams, ","),
+                                    StandardCharsets.UTF_8
+                                );
                             } catch (IOException ioe) {
                                 LOGGER.error("Could not create feeder file for operationId" + operation.getOperationId(), ioe);
                             }
@@ -358,7 +363,11 @@ public class ScalaGatlingCodegen extends AbstractScalaCodegen implements Codegen
             operation.addExtension("x-gatling-" + parameterType.toLowerCase(Locale.ROOT) + "-params", vendorList);
             operation.addExtension("x-gatling-" + parameterType.toLowerCase(Locale.ROOT) + "-feeder", operation.getOperationId() + parameterType.toUpperCase(Locale.ROOT) + "Feeder");
             try {
-                FileUtils.writeStringToFile(new File(outputFolder + File.separator + dataFolder + File.separator + operation.getOperationId() + "-" + parameterType.toLowerCase(Locale.ROOT) + "Params.csv"), StringUtils.join(parameterNames, ","));
+                FileUtils.writeStringToFile(
+                    new File(outputFolder + File.separator + dataFolder + File.separator + operation.getOperationId() + "-" + parameterType.toLowerCase(Locale.ROOT) + "Params.csv"),
+                    StringUtils.join(parameterNames, ","),
+                    StandardCharsets.UTF_8
+                );
             } catch (IOException ioe) {
                 LOGGER.error("Could not create feeder file for operationId" + operation.getOperationId(), ioe);
             }