eSIMzero is a company that delivers data communications services to travellers. While we may not produce all the component parts of our services ourselves, we take responsibility for the services we provide to you, so we will consult with our suppliers to ensure that any problems with their services are resolved promptly. 

We make every effort to ensure that our customers are happy with the level of service, and the products and services they receive from us. However, despite our best efforts, things can go wrong. We take customer complaints very seriously and aim to resolve them quickly and efficiently. 

If you have a complaint about any part of our service, please contact our Customer Teams using one of the following: 

  • By Email: contact@esimzero.com

  • Our Website: www.help.esimzero.com

  • By Letter: Across The World Mongolia Limited, 14 Old Queen Street, London, SW1H 9HP

Please note that complaints submitted by post will take longer to acknowledge than all other contact methods. 

If you make your complaint in writing, we will acknowledge receipt, advise how and when we will next respond and provide you with a contact point for checking progress on the resolution of your complaint. 

We will try to resolve your complaint quickly and efficiently, and to keep you informed at all times. We normally aim to resolve complaints within 10 working days but, depending on the nature of the complaint, this is not always possible. However, if you are not happy with progress in resolving your complaint you can ask the person to whom you are speaking to escalate the matter to the Complaint Escalations Team. If we cannot resolve the problem, we will write to you to say so.