Make a formal complaint to your broadband provider

Generate a tailored, formal complaint letter in seconds — for slow speeds, outages, missed appointments, billing or price rises. Fill in a few details and copy or download your letter. If your provider doesn’t resolve it within 6 weeks (or sends a deadlock letter sooner), you can escalate free to an independent ombudsman.

Last updated: 14 June 2026 · Written by The NetSorted team

Your letter

Fill in your name, the provider, what’s gone wrong, what you want to happen to copy or download the letter.

19 September 2026

Dear Your provider Complaints Team,

Re: Formal complaint — Broadband speed below what I am paying for

I am writing to make a formal complaint about the broadband speed I am receiving being persistently below what I was promised.

Describe what has gone wrong here.

To put this right, I would like: state what you would like to happen.

Please treat this as a formal complaint and respond in writing. If it is not resolved, I understand I can refer it to an independent alternative dispute resolution (ADR) scheme once it has been at least 6 weeks since this complaint, or sooner if you issue a deadlock letter.

Yours faithfully,
Your name

How to complain and escalate

Complain to your provider first

Send your complaint in writing (this tool creates it) and keep a copy. Note the date — it starts the clock.
Give them a chance to fix it

Keep records of every call and reply, including names, dates and reference numbers.
Escalate to ADR after 6 weeks

If it’s unresolved after 6 weeks — or sooner if they send you a “deadlock letter” — you can take it to a free, independent alternative dispute resolution (ADR) scheme.
Use the right ADR scheme

Your provider belongs to one of two Ofcom-approved schemes: the Communications Ombudsman or CISAS. Ask which, or check their website, then submit your case for free.

Frequently asked questions

How do I complain about my broadband provider?

Put your complaint in writing, clearly stating what went wrong, when, what you’ve already done, and what you want to happen. Keep a copy and records of all contact. This tool generates a tailored letter you can copy or download.

What if my provider doesn’t resolve my complaint?

If your complaint isn’t resolved after 6 weeks, or your provider sends you a “deadlock letter” sooner, you can escalate it for free to an independent alternative dispute resolution (ADR) scheme — either the Communications Ombudsman or CISAS, depending on your provider.

Is the complaint letter free to use?

Yes. The letter is generated entirely in your browser — nothing you type is sent to us — and you can copy or download it for free.

Can I claim compensation in my complaint?

Yes. If you’ve had a loss of service, missed appointments or a delayed activation, you may be owed automatic compensation — estimate it with our compensation calculator and mention the figure in your desired outcome.

Sources

Ofcom — Making a complaint and using ADR schemes — checked 14 June 2026