Which ombudsman handles my provider — CISAS or the Communications Ombudsman?

You have complained, nothing has happened, and someone has told you to “go to the ombudsman”. Two questions follow: which ombudsman, and when are you allowed to go?

Both have exact answers. There are two schemes, every UK provider must belong to one of them, and the waiting period changed in April 2026 — which is why most of the advice you will find on this still says eight weeks.

Which scheme does my provider belong to?

Ofcom approves two: the Communication & Internet Services Adjudication Scheme (CISAS), run by CEDR, and the Communications Ombudsman, which was called Ombudsman Services until July 2023. This is Ofcom’s own list, read on 29 August 2026.

Provider	Scheme
BT	Communications Ombudsman
EE	Communications Ombudsman
giffgaff	Communications Ombudsman
iD Mobile	Communications Ombudsman
Lebara	Communications Ombudsman
Lyca Mobile	Communications Ombudsman
NOW	CISAS
O2	CISAS
Plusnet	Communications Ombudsman
Sky	CISAS
SMARTY	CISAS
TalkTalk	CISAS
Tesco Mobile	Communications Ombudsman
Three	CISAS
Utility Warehouse	Communications Ombudsman
Virgin Media	CISAS
Vodafone	CISAS
VOXI	CISAS

Three things worth knowing, because they are where other pages go wrong.

Three and SMARTY only moved recently. CISAS’s own notice says it can review complaints about Three and Three Business from 21 May 2026, and about SMARTY from 27 May 2026. Any guide written before the summer is likely to have all three in the wrong column.

Business accounts do not always follow the residential brand. CISAS states that it cannot accept complaints for Virgin Media Business or O2 Business (O2 Daisy) customers, because those go to the Communications Ombudsman — so a small business with fewer than 10 employees on one of those accounts goes to the opposite scheme from the household next door. VOXI is handled under Vodafone on the CISAS system rather than as a brand of its own.

Your broadband and your mobile can be in different schemes. It is the provider that belongs to a scheme, not you. BT broadband and a SMARTY SIM means two schemes and two separate cases.

What if my provider is not on that list?

It is still in one of the two. Membership is not a choice a company makes: under General Condition C4.3, providers “are obliged to be a member of, and comply with, an approved alternative dispute resolution (‘ADR’) scheme”. Ofcom can impose a penalty of up to ten per cent of turnover for failing to comply with a formal notification about General Condition C4.

Ofcom’s published list covers the big names. For a smaller provider — an altnet, a regional network, a small MVNO — there are two first-party lookups:

• CISAS publishes a list of companies covered. If your provider has told you it is a CISAS member but it is not on that list, CISAS asks you to contact them.
• The Communications Ombudsman has a page per provider telling you whether it can review your dispute. If your provider is not there at all, the Ombudsman’s own FAQ says you may need to contact CISAS instead.

One trap: the Ombudsman’s “Providers A–Z” is a routing directory covering both schemes, not a membership list. It includes Sky, TalkTalk, Vodafone, Three and O2, all of which are CISAS. Use the per-provider page, which gives a yes or no.

One address caution. cisas.org.uk still works — it redirects to the live CISAS pages on CEDR’s site. But www.cisas.org.uk does not: it resolves to a different host that accepted no connection at all when we checked on 29 August 2026. If a link takes you nowhere, drop the www.

When am I actually allowed to go?

You can take a complaint to an ADR scheme if all of these are true:

• you are a residential customer, a small business of up to 10 employees, or a not-for-profit where up to 10 individuals work, not counting volunteers;
• you have already raised the complaint with your provider and it is still unresolved;
• it has been at least six weeks since you made the initial complaint, or you have been unable to reach agreement and have received a deadlock letter; and
• it has been less than 12 months since you received that deadlock letter.

Six weeks, not eight. Ofcom reduced the waiting period for complaints raised on or after 8 April 2026, and the change was deliberately not retrospective — CISAS still holds pre-8-April complaints to eight weeks. In practice that no longer bites: eight weeks from 8 April 2026 expired on 3 June 2026, so anything you complained about before the change has passed both thresholds by now. It matters mainly as the reason so much published advice still says eight.

CISAS — not the Ombudsman — has a third way in, and almost nobody publishes it. Rule 1.5.3 of its Scheme Rules lets you apply where “the Customer has not been able to complain to the Company because they have not been able to contact them, despite making reasonable efforts to do so (generally, contact must be made via a method set out in the Company’s complaints procedure)”. So if your provider has become genuinely unreachable — the number rings out, the webform bounces, the chat never connects — you are not necessarily stuck waiting six weeks for a complaint you were never able to lodge. Note the qualifier: your attempts should have used the routes the provider’s own complaints procedure sets out.

The deadlock letter is the part most people miss

A deadlock letter is your provider confirming it cannot take the complaint any further. CISAS also calls it a “final response” letter. It matters because it removes the wait entirely: with one in hand you can go to the scheme today.

The part almost nobody says out loud is that you can ask for one. Ofcom’s own eligibility wording carries the parenthesis “(you can request this)”. You do not have to wait for a provider to volunteer it, and providers rarely do.

Be realistic about it, though. Neither scheme guarantees you will get one: the Communications Ombudsman says only that you “may receive a letter or email” from your provider saying it can do no more, and CISAS simply describes what such a letter is called if it arrives. So if you are three weeks into a complaint and the conversation has clearly stopped, ask in writing for a deadlock letter and say you intend to take the matter to your provider’s ADR scheme. Two useful things can happen: either the letter arrives and you skip the wait, or the request lands with someone who would rather fix it than issue one.

Getting a deadlock letter does not oblige you to use it. CISAS is explicit that it means you can go to the scheme if you wish, and you remain free to seek other means of redress.

Can Ofcom just sort my broadband out?

No, and this is the most common misunderstanding in the whole area. Ofcom’s own words on its consumer help page are:

We don’t have powers to investigate or resolve individual complaints.

Ofcom regulates the industry, sets the General Conditions, publishes the schemes’ performance figures and can fine companies. It does not act as your representative. What it does ask is that you report faults and delayed repairs through its monitoring form, because that is how it spots patterns and acts on wider problems. Worth two minutes — it is just not the thing that gets your account credited.

The body that can order your provider to do something is the ADR scheme.

What can each scheme actually make my provider do?

Both are free to you and neither needs a solicitor. CISAS decides on documents alone — it says outright that there is no hearing and that the adjudicator has no direct contact with either side. The Communications Ombudsman also decides on the evidence both sides file, but it works differently in practice: you are assigned a named Dispute Resolution Executive you can contact through its portal, and you can register a dispute by telephone as well as online, by post or by email.

	CISAS	Communications Ombudsman
Run by	CEDR Services Ltd	Communications Ombudsman Ltd
Cost to you	Free — “as per the Communications Act 2003”	Free
Maximum award	£10,000 including VAT, covering compensation, refunds, credits and waivers together	£10,000 as a total award, already including any corrective action and goodwill award
Other remedies	A written apology, provide a service, do something about your bill, take an action it can reasonably carry out	Credit or cancel your account, fix the problem, apologise, recommend changes for the future
How it is decided	A legally trained adjudicator, on documents only, with no contact with either side	A named Dispute Resolution Executive, once both sides have filed evidence, with a 14-day evidence window
Target timescale	A final decision within 6 to 8 weeks of accepting a completed application	Says most disputes are resolved in under six weeks on average; complex cases can take longer
Ofcom-measured performance, Apr–Jun 2026	97% of decisions within six weeks	99% of decisions within six weeks (rounded up)
Your deadline to accept	30 working days	—
Provider’s deadline to act	20 working days from your acceptance	28 days
Can it fine your provider?	No — “CISAS is not a regulator and cannot impose fines or other sanctions”	No — it cannot punish providers or issue fines

The performance figures are Ofcom’s, published quarterly, and were the most recent it had at the end of August 2026. Ofcom sets both schemes the same target — more than 95% of case decisions reached within six weeks of the case being accepted — so this is one standard measured twice, not two different promises. Read the two-point gap as close to a tie: Ofcom flags the 99% as rounded up to the nearest whole percentage, and the two schemes are counting different things (see below).

Two details in that table are easy to blur and should not be. The compliance deadlines genuinely differ: 20 working days at CISAS, 28 calendar days at the Ombudsman. And Ofcom flags a structural difference behind the performance figures — for CISAS the decisions counted are its final decision, whereas for the Ombudsman they represent the point at which an initial decision is issued.

One more, because the numbers collide: CISAS’s “approximately 6–8 weeks” is how long a case takes once accepted. It is not the waiting period before you can apply. Two different six-week figures, in the same process, meaning different things.

How to escalate, in order

Follow these in sequence. Most of the work is in the first three.

1. Make it a formal complaint, not a support call. Use the provider’s formal complaints process and get the date and a reference in writing. Every provider must publish a complaints code of practice with a phone number — free to call or charged at the same rate as a geographic number — a postal address, and an email address or webform.
2. Find out which scheme covers your provider from the table above, from the CISAS list of companies covered, or from the Ombudsman’s page for that provider.
3. Keep a dated record while you wait. When the problem started, whether it is constant or intermittent, every contact and what you were promised. Ofcom asks people to send their provider a record of when the service dropped and how long each interruption lasted — and that record is exactly what an adjudicator reads later.
4. Ask for a deadlock letter if the complaint has visibly stalled. In writing.
5. Otherwise wait out the clock from the date you first complained — six weeks if that date was on or after 8 April 2026, eight weeks if it was before.
6. Submit the claim, and say what outcome you want — a credit, a refund, a repair, a cancellation without a fee, an apology. Be specific: the adjudicator directs a remedy, so it helps to know which one you are asking for.
7. Answer the provider’s response. It replies, you comment. It may offer a settlement first; you can accept or refuse.
8. Accept the decision in time. CISAS gives you 30 working days and says plainly that if you do not accept within that window the company is not obliged to take any action. A decision you sit on is a decision you lose.

If you do not like the decision

This differs by scheme, and it matters.

CISAS has no appeal. You can only accept or reject the adjudicator’s decision, and there is no process for appealing or changing the outcome.

The Communications Ombudsman does have one, in narrow circumstances: it says that if you disagree with its decision you may be able to appeal, in a limited number of cases — if new evidence has come to light since you submitted your dispute, or if a material error has been made. If you are a BT, EE, Plusnet, giffgaff, iD Mobile, Lebara, Tesco Mobile, Utility Warehouse or Lycamobile customer, that route exists and is worth asking about before you walk away.

Either way, rejecting is not the end of the road — a rejected decision simply has no effect, and you can still make a claim in the courts. What you cannot do is accept late. Thirty working days at CISAS is a hard stop.

What to do while the clock runs

Six weeks is a long time to sit with a broken service, and nothing about the ADR process stops you doing the other things you are entitled to do at the same time.

• Keep reporting the fault. Payment for a delayed repair under Ofcom’s automatic compensation scheme runs from when you report it, not from when it broke — so reporting today is worth more than complaining about yesterday. Our automatic compensation guide covers what is owed and when.
• Say if someone in the household is vulnerable. Ofcom advises telling your provider if you rely on the connection for telecare or healthcare devices or alarms, or if someone in the household is vulnerable — you might qualify for priority fault repair, and your provider can help you register for it.
• Put the complaint in a form that is hard to brush off. Our complaint letter generator builds one with the dates, the reference and the remedy stated — which is also most of what you will hand the adjudicator later.

Related

• How to complain about your broadband — the earlier steps, before escalation is on the table.
• Broadband automatic compensation — what your provider owes you without being asked.
• Mid-contract price rises and your right to leave — a different route out, with different rules.

→ Use the complaint letter generator