Complain to your provider in writing first. Since 8 April 2026 you can take an unresolved complaint to a free ombudsman after 6 weeks, or sooner if your provider sends a deadlock letter.
Checked 7 October 2026Written by the MyBillChecker team
Step by step
Complain in writing and keep a copy. Ask for a complaint reference number.
Give your provider 6 weeks, or ask for a deadlock letter if it says it can't help.
Find your provider's ombudsman scheme. Every provider belongs to one of two: the Communications Ombudsman or CISAS. It's on your bill or the provider's website.
Apply for free, within 12 months of the deadlock letter.
Template: mobile bill complaint
Template letter
Subject: Formal complaint, account [number]
My bill dated [date][describe the problem: a charge, price or fee you dispute]. My contract says [what it says]. Please [refund £X / correct the bill / remove the charge]. If this isn't resolved within 6 weeks, I'll refer it to your ombudsman scheme.
