My internet has stopped completely — what do I check?

A short sequence that tells you within minutes whether the fault is the line, the router or one device — and stops you resetting things that were never the problem.

Difficulty: beginner
Time: 20 min
Read: 4 min

Short answer

Look at the router's internet light, not the wifi light. If it is off, red or flashing, the fault is the line or the provider and nothing you change on a device will help. If it is steady, the line is fine and the fault is between the router and your devices.

Almost all wasted time here comes from working on the wrong link. The router tells you which link has failed before you touch anything, and that one glance changes what you should do next.

No internet — working out where the fault is

Step by step

Look at the router's internet or broadband light.Not the wifi light, which only says the router is broadcasting. Manufacturers use different words, but there is always one light for the connection to the outside world. Steady is good; off, red or flashing is not.
If that light is wrong, check the provider's status page on mobile data.Turn wifi off on your phone first so it genuinely uses mobile data. Most providers publish an outage checker, and many will already know about a fault in your area.
Check the physical connections.Power at the router, and the cable from the wall socket or fibre box seated at both ends. Cables get nudged by hoovers and by pets far more often than anything actually fails.
Restart the router once, and wait.Power off at the plug, count to thirty, power on. Then leave it a full five minutes; a full fibre or copper line has to resync before the internet light settles. Restarting repeatedly proves nothing.
If the internet light is steady, stop blaming the line.A healthy internet light means the router is talking to the provider. From here the fault is on your side of the router, which is a completely different set of checks.
Work out whether it affects everything or one device.Try a phone, a laptop and a television. One device failing while the rest work is a device problem. Everything failing at once points at the router or the wifi it is broadcasting.
Test with an ethernet cable if you can.Plug a laptop or a games console straight into the router. Working over cable but not over wifi narrows the problem to the wireless side, which is usually interference, a stuck radio or a duff channel.
For a single device, forget the network and rejoin it.Also check it is not stuck in aeroplane mode, not connected to a VPN that has failed, and not silently joined to a neighbour's network or a mobile hotspot it remembers.
Report it once you have proof.Tell the provider what you observed, not what you guess: which light, what colour, whether ethernet worked, how long it has been down. It shortens the call considerably and starts the clock for compensation.

Tips

Photograph the router's lights when everything is working. Comparing against a known-good picture is much faster than reading a manual during an outage.
Keep an ethernet cable in the drawer specifically for this test. It is the single fastest way to split a wifi problem from a broadband problem.
A total loss of service that is not fixed quickly may attract automatic compensation from the major UK providers.

Common mistakes

Pressing the reset pinhole on the router — That is a factory reset, not a restart. It wipes the wifi name and password back to the printed defaults, so every device in the house then has to be rejoined — while the original fault is usually still there.
Changing settings during an outage — If the outage was the provider's, you now have an unfamiliar configuration and no way to tell what fixed it. Change nothing until you know where the fault sits.

If it doesn't work

Internet light flashing and never settling

Cause: The line is not syncing — a fault outside the house, or a damaged cable inside it — Fix: Try the master socket directly if you have one, remove extension leads and filters, then report it. Repeated flashing is a line fault, not a wifi one.

Wifi connects but pages will not load

Cause: The router is broadcasting fine but has no connection onward, or a DNS problem — Fix: Check the internet light. If it is healthy, restart the router once, then try a different website to rule out a single site being down.

Everything works except one laptop

Cause: A device-level problem: stale network settings, a failed VPN, or a security tool blocking traffic — Fix: Forget and rejoin the network, disable any VPN, restart, and as a last resort reset that device's network settings.

Router lights normal but no wifi appears anywhere

Cause: The wireless radio has been switched off, sometimes by a scheduled 'quiet hours' setting — Fix: Check for a wifi button on the router and for a schedule in the router's app or admin page — providers often ship these on by default.

Questions people ask

How long should I wait before reporting it?

If the internet light is clearly wrong and the provider shows no known outage, report it after one restart. There is nothing to gain from waiting, and reporting starts the clock on any compensation.

Should I use my phone's hotspot in the meantime?

Yes, for essentials. Watch the data allowance, because video calls and cloud backups will empty it quickly. Turn off automatic backups and updates on anything using the hotspot.