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

[Today’s date]

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