How to Check if Your UK Broadband Is Slower Than Advertised and Claim a Refund
Your package promised speeds "up to" 67Mbps. Tonight it is delivering 6, and a half-hour programme has taken twenty minutes to buffer. Before you ring your provider and get talked in circles, it helps to know exactly what you were promised, how to measure what you are actually getting, and which rules your provider has signed up to. Done properly, this process often ends with a discount, a free upgrade, or a clean exit from the contract with no early termination fee.
Start With What Your Provider Promised
Broadband advertising in the UK is not allowed to quote a headline speed that fewer than half of customers actually receive at peak times. So the number on the advert is an average, not a promise to you personally.
What matters more is the speed estimate you were given when you signed up. Most major providers follow Ofcom's Broadband Speeds Code of Practice, which requires them to give you:
- a personalised estimate of the download speed your line should support
- a range, usually written as something like "36 to 44Mbps"
- a minimum guaranteed speed — the floor your line should not fall below
Find yours. It is normally in your welcome email, your contract summary or the confirmation letter. If you cannot find it, ask the provider to confirm it in writing, by chat or email, so it is recorded. That minimum is the number everything else hinges on.
Run a Speed Test That Will Stand Up
One test at 11am on a laptop in the kitchen proves nothing. Providers will bat it away in seconds. You want a set of results that looks like evidence.
- Use an Ethernet cable. Plug a laptop directly into the router. Wi-Fi results are easy to dispute; wired ones are not.
- Test at peak time. Roughly 8pm to 10pm is when networks are busiest and when the rules bite hardest.
- Clear the line. Pause downloads, streaming, cloud backups and game updates, and switch off any VPN.
- Use more than one tester. Two or three reputable speed test tools, so a single odd result cannot be dismissed.
- Check the router's own sync speed. Your provider's app or the router's admin page usually shows the speed the line is syncing at. If that figure is healthy but your tests are slow, the problem is inside your home.
- Test across at least a week or two. A pattern of evening slowdowns is far more persuasive than a snapshot.
Rule Out Your Own Equipment First
Be honest here, because your provider will be. Wi-Fi is the culprit more often than the line. Thick walls, a router tucked behind the television, a device that only supports the older 2.4GHz band, or a decade-old laptop can all slash the speed that reaches your screen.
Try moving the router into the open, testing right next to it, swapping the Ethernet cable and trying a second device. On a fibre-to-the-cabinet service, check your microfilters and avoid long telephone extension leads, which are notorious for dragging speeds down. If a wired test next to the router is slow too, you have a genuine line problem — and a much stronger case.
Keep a Log You Could Show a Stranger
Set up a simple spreadsheet or notes file. For each test, record the date, the time, download and upload speeds, latency, whether you were wired or on Wi-Fi, and the device used. Add anything relevant: dropouts, calls to support, and what you were told.
Take screenshots. If you can, use a tool that logs results automatically over several days — the pattern of evening collapse is exactly what you are trying to show. Keep your guaranteed minimum speed at the top of that document so it is always in view.
What Ofcom's Rules Actually Give You
Under the Code of Practice, if your speed falls below the guaranteed minimum and stays there, the sequence providers are expected to follow is straightforward:
Report it. The provider has 30 days to fix the problem. If it cannot, you are entitled to leave the contract without paying an early termination charge.
That right to walk away is the main remedy, and it is a strong one. If you would rather stay, you can still push for a price reduction, a temporary discount, or an upgrade to a faster technology such as full fibre.
Separately, Ofcom's Automatic Compensation Scheme covers delayed repairs, missed engineer appointments and delayed installations. The amounts are fixed and reviewed periodically, so check Ofcom's current figures rather than relying on an old number. Note that slow speeds alone do not automatically trigger that scheme — it is about service failures and delays, not day-to-day performance.
Asking for a Refund Without Wasting Your Breath
Put the request in writing. Keep it short and factual: the speed you were promised, the speeds you have actually been getting, the dates, and what you want.
- Ask for a refund covering the months in which performance fell below your guaranteed minimum.
- Ask for a discount on your monthly bill until the fault is fixed, or a free upgrade.
- Ask them, in the same message, to confirm your right to exit penalty-free if the fault is not resolved within 30 days.
- Give a deadline — seven days is reasonable — and say what you will do next if there is no response.
Do not accept "up to" as an answer. You are not complaining about the headline figure; you are complaining about falling below the minimum they guaranteed you.
If They Stall, Escalate
Ask for a formal complaint reference. Providers normally have eight weeks to resolve a complaint. If they do not, or if they send you a deadlock letter, you can take the dispute to a free alternative dispute resolution service — CISAS or Ombudsman Services: Communications, depending on which one your provider uses. Their decision can be binding on the provider.
Ofcom itself does not settle individual disputes, but it does collect reports and publishes useful guidance on broadband speeds and complaints. If the sums involved are significant, Citizens Advice or a solicitor can tell you whether a small claim is worth pursuing. Check your rights rather than guessing at them.
The Short Version
Find your guaranteed minimum speed. Test wired, at peak times, repeatedly, and log every result. Fix your own Wi-Fi before blaming the line. Report the fault, hold them to the 30-day fix, and ask in writing for a refund or a penalty-free exit. If they drag their feet past eight weeks, escalate to the ombudsman scheme.
Most people who go through this end up with something: a discount, a better router, a faster package, or the freedom to switch provider. What they never get is anything at all if they never measure it in the first place.
