I have the very same issue. If I use this construct

throw new ResponseStatusException(HttpStatus.NOT_FOUND, "Error in update"); 

My message is not passed to client via JSON. For me, the only way to go around it was to create GlobalExceptionHandler class

package mypackage; import org.springframework.http.ResponseEntity; import org.springframework.web.bind.annotation.ControllerAdvice; import org.springframework.web.bind.annotation.ExceptionHandler; import java.util.Date; @ControllerAdvice public class GlobalExceptionHandler { @ExceptionHandler(NotFoundException.class) public ResponseEntity<ErrorDTO> generateNotFoundException(NotFoundException ex) { ErrorDTO errorDTO = new ErrorDTO(); errorDTO.setMessage(ex.getMessage()); errorDTO.setStatus(String.valueOf(ex.getStatus().value())); errorDTO.setTime(new Date().toString()); return new ResponseEntity<ErrorDTO>(errorDTO, ex.getStatus()); } } 

I have also created my own Exception type

package mypackage; import org.springframework.http.HttpStatus; public class NotFoundException extends RuntimeException { public NotFoundException(String message) { super(message); } public HttpStatus getStatus() { return HttpStatus.NOT_FOUND; } } 

With this, I am able to throw exception from the controller and I am getting proper result in JSON - the message I want to see.

@PutMapping("/data/{id}") public DataEntity updateData(@RequestBody DataEntity data, @PathVariable int id) { throw new NotFoundException("Element not found"); } 

I had to introduce ErrorDTO as well

package mypackage; public class ErrorDTO { public String status; public String message; public String time; ... ... // getters and setters are here ... ... } 

Update

As mentioned by @Hassan and @cunhaf (in comments under original question), the solution with

server.error.include-message=always 

works perfectly fine with ResponseStatusException. Still, solution with GlobalExceptionHandler might be better in case someone wants to pass more info via Exception.

Source code

Samples can be found here: Global Exception Handler

For those who are concerned about potentially leaking sensitive information with the application.properties recommended by the accepted answer, I found that there are additional options available for the server.error.include-message property.

Setting server.error.include-message=always will always include a reason when an exception is thrown, even if that reason potentially exposes sensitive information about your application.

A better option to use is server.error.include-message=on-param, which will only include a message when you explicitly set one via ResponseStatusException:

if (requestBody.someField == null) { throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "someField is required."); } 

Strangely, Spring Boot 2.6.x changed this behavior again and the error message set on ResponseStatusException is not returned. I had to downgrade to 2.5.6 in order to solve it. In the end I had something like this:

 @DeleteMapping("/{id}") @ResponseStatus(HttpStatus.OK) public MessageResponse deleteById(@PathVariable(value = "id") Integer id) { try { userService.deleteById(id); } catch (Exception e) { throw new ResponseStatusException(HttpStatus.EXPECTATION_FAILED, "Error deleting user. User has dependencies", e); } } 

there is bean that can be overridden to include custom message.

Normal Spring Boot: org.springframework.boot.web.servlet.error.ErrorAttributes

Spring Wedbflux: org.springframework.boot.web.reactive.error.ErrorAttributes

the default implementation is DefaultErrorAttributes.

You can override public Map<String, Object> getErrorAttributes(ServerRequest request, ErrorAttributeOptions options) {

the return make it return the message you want

In my case I created a decorator that will remove messages if it's internal server error:

public class CustomErrorAttributesDecorator implements ErrorAttributes { private final ErrorAttributes errorAttributes; CustomErrorAttributesDecorator(ErrorAttributes errorAttributes){ this.errorAttributes = errorAttributes; } @Override public Map<String, Object> getErrorAttributes(ServerRequest request, ErrorAttributeOptions options) { Map<String, Object> errorAttributesMap = this.errorAttributes.getErrorAttributes(request, options); if(HttpStatus.INTERNAL_SERVER_ERROR.value() == (int) errorAttributesMap.get("status")){ errorAttributesMap.remove("message"); } return errorAttributesMap; } ... } 

and then I created a @Bean as follows:

 @Bean ErrorAttributes customErrorAttributes(){ return new CustomErrorAttributesDecorator(new DefaultErrorAttributes()); } 

Starting from the 2.3 version, Spring Boot doesn't include an error message on the default error page. The reason is to reduce the risk of leaking information to a client

To change the default behavior, we can use a server.error.include-message property.

if you are making a REST API take a look at zalando-problem for exception handling. problem-spring-web

Evry exception is catched by @ExceptionHandler and you just have to return a Problem object using the zalando builder.

public class ResourceNotFoundException extends Exception { // ... } @ControllerAdvice public class MyExceptionHandler implements ProblemHandling { @ExceptionHandler(ResourceNotFoundException.class) @ResponseStatus(value = HttpStatus.NOT_FOUND) public ResponseEntity<Problem> handleResourceNotFoundException(final ResourceNotFoundException exception, final NativeWebRequest request) { Problem problem = Problem.builder()// .withType(URI.create("https://example.com/problem/not-found"))// .withTitle("Resource not found")// .withStatus(Status.NOT_FOUND)// .withDetail(exception.getMessage()).build(); } ... }