How to Complain to the Communications Ombudsman: UK Guide (2026)

At a glance

• Two Ofcom-approved schemes: Communications Ombudsman and CISAS (Communications and Internet Services Adjudication Scheme). Every telecoms provider must belong to one.
• Time to escalate: six weeks from the date you first raised the complaint with your provider — reduced from eight weeks by Ofcom from 8 April 2026 (Ofcom announcement).
• Deadlock letter: if your provider issues a deadlock letter before six weeks is up, you can escalate immediately. You then have 12 months from the date of that letter to bring your case.
• Free for consumers and small businesses: legally required under section 52 of the Communications Act 2003.
• Services covered: mobile, broadband, landline, and pay-TV.
• Decision is binding on the provider once you accept it; you retain the right to go to court if you reject it.

What is the Communications Ombudsman — and what is CISAS?

Ofcom is the regulator for the UK communications sector. Under section 52 of the Communications Act 2003, Ofcom is under a statutory duty to set conditions requiring every provider to offer domestic and small business customers access to an independent and free dispute resolution procedure. That duty is implemented through General Condition C4, which obliges every communications provider to belong to an Ofcom-approved ADR scheme.

There are currently two approved schemes:

• Communications Ombudsman — formerly known as Ombudsman Services: Communications, the scheme operates as a dedicated telecoms complaints body.
• CISAS (Communications and Internet Services Adjudication Scheme) — run by the Centre for Effective Dispute Resolution (CEDR), an internationally recognised ADR body.

Both schemes are independent of Ofcom and independent of the providers they oversee. Each investigates disputes by looking at what the contract says, what the provider actually did, and whether the outcome was fair under the applicable rules. They can award remedies binding on the provider; they cannot fine providers or set industry-wide policy — that remains Ofcom's role.

Your provider must tell you which scheme it belongs to. The information is usually in their complaints policy or on their website, and Ofcom also maintains a list at ofcom.org.uk/phones-and-broadband/service-quality/adr-schemes. If you approach the wrong scheme in error, your complaint will be redirected, not lost.

The 6-week rule — what changed in April 2026

The most important update for anyone raising a telecoms complaint right now is a rule change that came into effect on 8 April 2026. Following a review of ADR in the telecoms sector, Ofcom reduced the mandatory waiting period before a consumer can escalate to an ADR scheme from eight weeks to six weeks.

The change applies to complaints first raised with a provider on or after 8 April 2026. If you raised your complaint before that date and it has been running for more than eight weeks without resolution, the old eight-week rule applied to you — but practically speaking, if you are reading this after April 2026, the six-week period is now the operative rule for new complaints.

There are two distinct triggers. Either satisfies the eligibility test:

1. Six weeks have passed since you first formally notified your provider of the complaint without a satisfactory outcome, or
2. Your provider has issued a deadlock letter — a written statement that they have done everything they can and the dispute cannot be resolved between you — at any point, even before six weeks has elapsed.

A deadlock letter also starts a 12-month clock: you must bring your case to the scheme within 12 months of the date on the letter.

What disputes are covered

Both schemes handle complaints about the services their member providers supply to consumers and small businesses. The types of disputes they deal with include:

• Billing errors — charges applied incorrectly, direct debits taken for the wrong amount, or disputed usage charges
• Service quality — speeds significantly below what was contracted, repeated outages, or service that does not match what was sold
• Missed engineer appointments — engineers who did not attend or were significantly late, causing financial loss or inconvenience
• Early termination charges — where you believe a charge is not contractually justified or where the provider triggered the right to cancel
• Mis-selling — where you were given incorrect information about the service, price or contract terms before signing up
• Contract disputes — disagreements about renewal, notice periods, or what a contract actually provides

Both schemes will also look at complaints about pay-TV services where the provider is a scheme member. Neither scheme resolves complaints about Ofcom's own regulatory decisions, nor do they arbitrate on whether market pricing is generally fair — their focus is whether the provider met its obligations under your specific contract.

Step-by-step: how to make a complaint

Step 1 — Raise the complaint formally with your provider

Before any ADR scheme will accept your case, you must have raised a formal complaint with your provider and given them the opportunity to put things right. This is a legal requirement, not optional. Contact your provider through their official complaints channel (usually a dedicated phone number, email address, or online form — not a general customer service chat), state clearly that you are making a formal complaint, and ask for a written confirmation with a reference number. Keep records of every contact: dates, names of agents spoken to, and what was said.

Step 2 — Track the six-week period from your first notification

Your escalation right opens six weeks after you first notified your provider of the complaint (for complaints raised on or after 8 April 2026). Note the date you made first contact and count forward. If your provider offers a partial resolution before that point but you do not find it acceptable, you do not have to accept it — the six-week clock continues to run. Do keep a clear note of any offers made, as the scheme will consider whether any offers were reasonable.

Step 3 — Watch for a deadlock letter

If your provider sends you a written deadlock letter at any point before six weeks has elapsed, you can escalate immediately — you do not have to wait. The letter should include contact details for the relevant ADR scheme. Once you receive one, make a note of the date: your 12-month window to bring the complaint starts from that day.

Step 4 — Identify the correct scheme and submit your complaint

Check which scheme your provider belongs to (Communications Ombudsman or CISAS) and go to that scheme's website. Both allow complaints to be submitted online, but also accept post, email and telephone. You will need to provide:

• Your full name, address and account details
• The name of your provider and a brief summary of the service in dispute
• A clear account of what went wrong and when
• What you have already done to resolve the complaint and the provider's response
• What outcome you are seeking

Be factual and specific. The investigator is not starting from scratch — they will also ask the provider for their account of events and any relevant records. Your job is to present your side of the story clearly and let the evidence do the work.

Step 5 — Gather and organise your evidence

The strength of an ADR complaint comes down to documentation. Pull together:

• Written correspondence — emails, letters, any written responses from your provider
• Bills and account statements — showing the charges you dispute
• Screenshots — of live chat transcripts, app messages, or online account pages
• Call records — dates, times and duration of calls (most providers log these and can supply them on request)
• Contract terms — the agreement you signed, including any promotional materials if mis-selling is alleged
• Engineer visit records — appointment confirmations and any notes left after a visit
• Photographs or speed test results — if poor service quality is the issue, timestamped speed test results from a reliable testing tool are useful contemporaneous evidence

Organise everything chronologically so the investigator can follow the narrative without having to ask for clarification.

Step 6 — Respond to the investigation and receive the decision

Once your complaint is accepted, the scheme will request information from the provider, assess the evidence from both sides against the contract terms and applicable rules, and may come back to you with questions. Respond promptly. The scheme is required by Ofcom to resolve more than 90 per cent of cases within six weeks of acceptance.

When the decision is issued, you have a choice:

• Accept it — the decision becomes binding on the provider, which must comply. If the provider fails to do so, Ofcom can take enforcement action.
• Reject it — you are not bound by the decision and keep your right to pursue the matter through the courts. The court will not be told what the scheme decided.

If you are considering rejecting the decision, think carefully about the cost and effort of court proceedings relative to the gap between what was awarded and what you are seeking. For modest sums, the scheme's decision is often the most practical resolution available.

What remedies can the scheme order?

If the scheme finds in your favour, it can require the provider to:

• Issue a formal written apology
• Correct your account (remove incorrect charges or credit an account)
• Waive early termination fees or other disputed contractual charges
• Cancel a contract without penalty
• Arrange or rearrange a repair or installation
• Pay financial compensation for financial loss, distress or inconvenience

Financial awards are compensatory. They reflect actual loss and reasonable inconvenience rather than acting as a deterrent penalty against the provider. Schemes do not impose fines; that remains Ofcom's enforcement role.

Who is eligible — consumers and small businesses

Both schemes serve domestic customers and small business customers. For these purposes, a small business is one where no more than ten individuals work for that business, whether as employees, volunteers or otherwise. This definition is drawn from the Communications Act 2003 and reflected in General Condition C4. Businesses larger than this threshold are expected to pursue disputes through commercial channels or, if necessary, the courts.

If you are unsure whether your business qualifies, check the eligibility section on the relevant scheme's website before submitting.

A note on Ofcom's role

A common point of confusion is the difference between the ADR schemes and Ofcom itself. Ofcom does not resolve individual consumer complaints. Ofcom is the sector regulator: it sets the rules that providers must follow, approves and monitors the ADR schemes, and can take enforcement action against providers who breach those rules. If you believe a provider is systematically breaking the rules — or if a provider is not a member of any scheme at all — you can report that to Ofcom at ofcom.org.uk. Ofcom cannot award you compensation, but its enforcement activity can lead to providers improving their practices more broadly.

This guide covers the position in England, Wales and Scotland for telecoms and broadband complaints. It is not a substitute for legal advice on your specific circumstances. The law and Ofcom rules described were accurate as at June 2026 and are subject to change. The six-week rule applies to complaints first raised with providers on or after 8 April 2026.

Last reviewed: June 2026 · Next review due: June 2027 or on Ofcom rule change.