How to complain about slow broadband in the UK

Start with repeatable evidence, then follow the provider’s published complaints route. Keep a paper trail, ask for a final written outcome, and only then look at alternative dispute resolution (ADR). Rushing straight to social media without dates rarely fixes line speed.

Not legal advice—check your contract and provider terms.

Evidence checklist

Action path

  1. Collect dated Pulse or other fair tests across multiple days, ideally including one Ethernet run.
  2. Raise a fault first if you have not; keep ticket numbers and engineer visit notes.
  3. Submit a formal written complaint with evidence and your desired outcome.
  4. If unresolved after the provider’s final position, contact the approved ADR scheme listed for your ISP.

When to escalate

ADR is for deadlocks after the ISP process, not for day-one grumbles. A homeowner in Kent waited for the written “final response,” then contacted ADR with the same evidence pack—much clearer than mixing threads across chat apps.

How Pulse relates to this topic

Pulse gives you structured, browser-based readings you can log alongside timestamps. It is not a regulator and does not replace your ISP’s own tests—but it helps you describe behaviour clearly.

Run the Pulse speed test · Read methodology · Review privacy

FAQ

How much evidence should I collect?

Several days of fair tests—wired where possible—with dates, times, and what else was using the line.

When can I escalate?

After you have a final response from the provider or their complaints deadline passes, you may be able to go to ADR.

What should I put in a formal complaint?

A short timeline, your minimum speed or contract references, what you want fixed, and attachments for proof.

Should I cancel mid-complaint?

Be careful with contract terms; document advice from the provider before changing service while a dispute is open.

Sources and review notes

Last reviewed: 11/04/2026 · Written by: Dr Alex J Martin-Smith (LinkedIn)

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