How to Complain About Your Broadband Speed (UK Rights Guide)

If your broadband consistently falls below what your ISP promised, you have real legal rights in the UK. Ofcom's voluntary code of practice, followed by all major ISPs, gives you a clear process for getting the problem fixed — or escaping your contract without paying exit fees.

Your Legal Rights

Under the Ofcom Broadband Code of Practice (voluntary but followed by BT, Sky, Virgin, TalkTalk, EE, Vodafone, and Plusnet), your ISP must:

• Provide a Minimum Guaranteed Speed at point of sale — a specific Mbps figure below which they're obligated to fix your connection
• Give you options if your speed consistently falls below this minimum
• Allow you to exit your contract penalty-free if they cannot fix it within 30 days

Your Minimum Guaranteed Speed was quoted when you signed up and should be on your order confirmation. If you can't find it, call your ISP and ask them to confirm it in writing.

Step 1: Document the Problem Properly

Before contacting your ISP, build a solid evidence case. This makes it much harder for them to dismiss your complaint.

1. Run speed tests at multiple times of day for at least a week. Use our speed test tool. Test in the morning, afternoon, and again at peak hours (7–9pm). Record each result with the date and time.
2. Test with a wired Ethernet connection. Plug your laptop directly into the router. ISPs are entitled to dismiss Wi-Fi slowdowns as a device issue. Wired results prove it's the line, not your device.
3. Test on multiple devices. If the slow speed appears on multiple devices (wired), it rules out a device-specific problem.
4. Note any outages or recent changes. Record when the problem started and any correlation with ISP changes or extreme weather (wet cable issues affect copper lines).

Step 2: Contact Your ISP

Call or chat with your ISP's technical support, armed with your evidence. Be clear and specific:

• State your Minimum Guaranteed Speed and the speeds you've actually measured
• Specify that you've tested wired via Ethernet
• Request they run a line test from their end
• Ask them to send an engineer if the remote line test doesn't identify the cause
• Get a reference number for every call and ask them to confirm actions in writing (email or letter)

ISPs are usually helpful at this stage. Most speed issues are caused by line faults, faulty microfilters, or exchange-level problems that engineers can fix. Give them the opportunity to resolve it first.

Step 3: Make a Formal Complaint

If the problem persists after an engineer visit or they dismiss your claim without adequately investigating it, escalate to a formal written complaint.

• Write to or email the provider's complaints team (find the address on their website)
• Include all your speed test results, dates, and reference numbers from previous calls
• State clearly that you're making a formal complaint under Ofcom's Code of Practice
• Request a written response within 14 days

At this point, the clock starts ticking. Under the Ofcom code, they have 8 weeks to resolve your complaint before you can take it to an alternative dispute resolution (ADR) service.

Step 4: Escalate to the Ombudsman

If your ISP fails to resolve the problem after 8 weeks, or issues a "deadlock" letter, you can take the case to the independent Communications Ombudsman (CISAS or Ombudsman Services: Communications — depending on your ISP's membership).

This service is:

• Free for consumers
• Independent and legally binding on the ISP
• Able to award compensation and require remedial action

The Ombudsman processes tens of thousands of cases per year and finds in favour of consumers in a significant proportion. ISPs take Ombudsman cases seriously because adverse findings cost money and damage their Ofcom performance metrics.

Exiting Your Contract for Free

If you're within a minimum contract term and your speeds consistently fall below your Minimum Guaranteed Speed, and the ISP cannot fix the problem within 30 days of you first reporting it, you are entitled to exit the contract without paying an early termination charge.

To exercise this right:

1. Formally report the speed problem to your ISP (creating a paper trail)
2. Give them 30 days to resolve it
3. If speeds remain below the guaranteed minimum after 30 days, write to them stating you're exercising your right to exit under Ofcom's Code of Practice
4. Do not simply cancel by direct debit — follow the formal process so you have written confirmation you're not liable for exit charges