How to File a Complaint?

At SUMOSIM, we value our customers and are committed to providing the highest level of service. However, we understand that sometimes issues may arise, and we are dedicated to resolving any concerns you may have. This Complaints Policy outlines how to submit a complaint, how we handle complaints, and the steps we take to address your concerns.

How to File a Complaint?

If you have a complaint, we encourage you to contact us as soon as possible so we can address the issue promptly. You can file a complaint using the following methods:

• Online chat
• Via Email: complaints@sumosim.com

Please include as much detail as possible in your complaint, such as:

• Your name and contact information
• The nature of the complaint
• Any relevant account details (e.g., account number, service dates, etc.)
• A description of what happened and how it has affected you
• Any steps you have already taken to resolve the issue

Prefer to send a letter?

If you’d rather write to us, please post your complaint to:

Complaints Team 

SUMOSIM LTD,

71-75 Shelton Street,

Covent Garden,

WC2H 9JQ

When you write to us, please include your account details so we can find your information quickly. One of our team members will get in touch with you by email, phone, or post (if you prefer) within 8 weeks of receiving your letter.

For most issues, we aim to resolve your complaint within 5 business days. If your concern is more technical or complex, it may take us a bit longer while we investigate thoroughly. We’ll keep you updated along the way, just enough to keep you informed without overwhelming you.

If we’re unable to resolve your complaint within 8 weeks, we will share details on how you can contact the Communications Ombudsman, who can look into complaints that have been open for over 8 weeks or where we’ve reached a deadlock.

A deadlock means we’ve tried everything to resolve your complaint, but we can’t reach an agreement with you. If you think your situation qualifies, you can request a deadlock letter from the SumoSim team managing your complaint. If we’re still actively working on a resolution or your issue falls outside the Ombudsman’s remit, we won’t issue a deadlock letter.

Please note: We, and the Ombudsman, will not respond to complaints that are deemed futile.

We genuinely want to sort things out for you and avoid any hassle, so if we’ve missed the mark, please give us the chance to make it right.

Updated on: 27/06/2025