How to write to the phone or broadband ombudsman

Which scheme covers you

Ofcom approves two independent schemes for phone, mobile and broadband complaints. One is the Communications Ombudsman, which was called Ombudsman Services until 2023. The other is CISAS, run by the Centre for Effective Dispute Resolution.

Providers pick which scheme to join, and that decision is what determines where your complaint goes. You do not get a say, and the type of product makes no difference either: a mobile complaint and a broadband complaint about the same company go to the same place.

Two wrinkles worth catching before you write. Business accounts can split away from residential ones at the same brand, so Virgin Media and O2 sit with CISAS for home customers and with the Communications Ombudsman for business. And if you were a Shell Energy Broadband customer, that brand no longer exists: those accounts moved to TalkTalk, so a complaint about it now goes to CISAS.

The six week rule

You cannot go straight to a scheme. You have to complain to your provider first and give it a chance to put things right. The wait used to be eight weeks and a great deal of advice still says so.

Since 8 April 2026 it is six weeks. Ofcom changed its rules that day, and the new wait applies to complaints raised on or after it. If you raised yours earlier, the old eight week clock still governs it. That single date is the difference between escalating on time and being told to come back later.

There is a second deadline at the other end. If your provider sends you a letter saying it cannot resolve things, you have twelve months from that letter to take the complaint to the scheme.

If you never got such a letter and you are relying on the six week route instead, neither scheme publishes a deadline running from the date you complained. That sounds like breathing room and is not one: CISAS will only take a complaint that is still live, so a dispute you let go cold can be refused on that basis. Apply once you are eligible.

The deadlock letter

A deadlock letter is your provider confirming in writing that it has finished with your complaint and will do nothing further. It is a shortcut: with one, you can escalate immediately rather than waiting out the six weeks.

A lot of advice tells you that you can demand one. Be careful with that. Ofcom's rules oblige a provider to send the letter when it has told you its answer, you have said the answer does not resolve things, and it does not intend to do anything else. The trigger is the provider's own position, not your request. Ofcom's consumer page does say you can ask for one, and asking is free, but a refusal is not a dead end.

Ofcom's own figures put this in proportion: only around 0.7 per cent of people get to a scheme early this way. For almost everybody the six week route is the real one, so if you are being stonewalled, note the date you first complained and wait it out rather than fighting over a letter you do not need.

What to put in the letter

Both schemes take your complaint through an online form rather than a posted letter, so what follows is really about what you write into the box. The schemes are deciding whether your provider acted fairly, so give them the facts that answer that question and little else.

1. Your account details. Account or mobile number, the address the service is at, and the name on the bill.
2. The date you first complained. This is the one that decides whether you are eligible at all, so put it near the top and be exact. A reference number if you have one.
3. What went wrong, in order. Dates, what you were promised, what happened instead. Keep it chronological. Resist the urge to write it as an argument.
4. What the provider said. Including any offer it made. The scheme can award less than you were already offered, so an offer on the table is worth weighing before you escalate.
5. What you want. Be specific and be realistic: the refund, the account credit, the service fixed, the contract ended without a fee.
6. Your evidence. Bills, screenshots of chat transcripts, engineer appointment texts, speed test results.

One trap that is easy to walk into and expensive. At CISAS the £10,000 ceiling is not just the most you can be awarded, it is the most you can ask for. An application claiming more than £10,000 in total, counting compensation, refunds, credits and waivers together, is excluded from the scheme altogether. Asking for a large round number to leave room for negotiation is how people lock themselves out.

For the letter to your provider that comes first, we have a separate walkthrough on complaint letters.

What they can award

Both schemes can order your provider to apologise, to take practical action such as fixing the service or cancelling a contract, and to pay you. The cap at both is £10,000.

Set your expectations by what actually gets paid rather than by the ceiling. The Communications Ombudsman pays what it calls a time and trouble award, typically £50 to £100, on top of putting the original problem right. CISAS says its adjudicators do not usually award more than £100 to £200 for inconvenience and distress. The substantial money, when there is any, is the refund of what you were wrongly charged.

Neither scheme can fine your provider, punish it, or tell it how to run its business. What they can do is order a remedy for you specifically. One quiet upside worth knowing: an adjudicator is allowed to award you more than you asked for.

Both are free to you. The provider pays the fees.

The deadline that voids it

This is the part that catches people who have already done everything else right. A decision in your favour is not binding on anyone until you formally accept it, and if you say nothing it lapses.

• CISAS: thirty working days to accept, and you cannot accept in part. Once the window closes the decision cannot be accepted at all, and there is no appeal.
• Communications Ombudsman: fourteen calendar days.

Those are genuinely different deadlines, so check which scheme you are in rather than assuming a month. Fourteen calendar days is a fortnight that includes a bank holiday weekend if you are unlucky.

Once you accept, your provider must comply: within twenty working days at CISAS, twenty eight days at the Communications Ombudsman. If you reject the decision instead, nothing binds either of you and you keep the right to go to court.

Money you should get without asking

Before you escalate anything, check whether you were owed automatic compensation and never received it. It is paid without you claiming, which is precisely why people do not notice its absence.

• £10.34 a day when your service stops working and is not fixed after two full working days
• £32.31for an engineer who does not turn up, or an appointment cancelled with less than 24 hours' notice
• £6.46 a day when a new service does not start on the promised date

Those rates apply to problems arising on or after 1 April 2026. They rise every April in line with inflation.

Two limits matter. The scheme is voluntary, so it only binds providers that signed up: BT, EE, Hyperoptic, Plusnet, Sky, TalkTalk, Utility Warehouse, Virgin Media, Vodafone, Zen Internet. And it covers landline and broadband only, which is why no mobile-only provider is on that list. Nobody is required by Ofcom to pay this.

If you should have been paid and were not, that is an ordinary complaint. Raise it with your provider, and the six week clock starts from the day you do. Our guide to broadband automatic compensation goes through the exclusions in more detail.