diff --git a/src/main/java/com/knecon/fforesight/tenantusermanagement/service/UserService.java b/src/main/java/com/knecon/fforesight/tenantusermanagement/service/UserService.java
index a5bfbeb..6ea260b 100644
--- a/src/main/java/com/knecon/fforesight/tenantusermanagement/service/UserService.java
+++ b/src/main/java/com/knecon/fforesight/tenantusermanagement/service/UserService.java
@@ -73,6 +73,10 @@ public class UserService {
     @CacheEvict(value = "${commons.keycloak.userCache}", allEntries = true, beforeInvocation = true)
     public User createUser(CreateUserRequest user) {
 
+        if (StringUtils.isEmpty(user.getEmail())) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Email address must be set");
+        }
+
         String username = StringUtils.isEmpty(user.getUsername()) ? user.getEmail() : user.getUsername();
         if (!this.getTenantUsersResource().search(username).isEmpty()) {
             throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "User with this username already exists");
diff --git a/src/test/java/com/knecon/fforesight/tests/UserTest.java b/src/test/java/com/knecon/fforesight/tests/UserTest.java
index aa59134..b05faad 100644
--- a/src/test/java/com/knecon/fforesight/tests/UserTest.java
+++ b/src/test/java/com/knecon/fforesight/tests/UserTest.java
@@ -133,5 +133,23 @@ public class UserTest extends AbstractTenantUserManagementIntegrationTest {
         }
 
     }
+    
+    @Test
+    public void testCreateUserWithoutMail() {
+
+        TenantContext.setTenantId(AbstractTenantUserManagementIntegrationTest.TEST_TENANT_ID);
+
+        CreateUserRequest createUserRequest = new CreateUserRequest();
+        createUserRequest.setFirstName("Test");
+        createUserRequest.setLastName("New User");
+        createUserRequest.setUsername(createUserRequest.getEmail());
+        createUserRequest.setRoles(tenantUserManagementProperties.getKcRoleMapping().getAllRoles());
+        try {
+            userClient.createUser(createUserRequest);
+        } catch (FeignException e) {
+            assertThat(e.status()).isEqualTo(400);
+        }
+
+    }
 
 }