Broadband down? First prove whether the whole service is offline or only Wi‑Fi has failed. Then check the router, Openreach ONT or copper line, account status and provider network in the right order.
No internet connection guide
Separate a Total Outage from Wi-Fi or Device Failure
Use multiple devices, Ethernet, router and ONT lights, cable checks and provider status to identify whether the connection is down inside or outside the home.
This runs entirely in your browser and does not send your answers anywhere. Choose the closest match; the result points you to the shortest diagnostic path on this page.
Choose the right physical path
Full Fibre ONT or copper / FTTC master socket?
Do not use copper-line tests on a full-fibre-only connection. The physical handoff tells you which checks are relevant.
Section A — Full Fibre / FTTP
If you have a small white Openreach fibre box (ONT) on the wall: check its PON, LOS and LAN/PORT lights, then the Ethernet lead from ONT to router WAN. If you searched for an “optical patch lead click” after the fibre lead was moved, do not unplug, clean or force the optical connector yourself; check only for obvious looseness, sharp bends or tension and preserve a red LOS state for the provider.
If the router plugs into an Openreach phone socket: check DSL sync, a known-good filter/lead and the NTE5C or compatible master test socket.
If you still have an active analogue phone line, no dial tone or persistent crackling is useful fault evidence. This clue does not apply to Digital Voice.
Quick fix checklist
Broadband down? Try these four checks first
Use these safe checks before deeper line diagnostics. Record unusual router or ONT lights before restarting anything.
01
Check more than one device
If only one device fails, it is probably not a total broadband outage. Compare another phone, computer or TV.
02
Record service lights
Note the exact Internet/DSL, PON, LOS and LAN/PORT colours or flash patterns before changing power.
03
Check power and cables
Reseat power, WAN, Ethernet or DSL leads. Never bend, pull or look into the end of a fibre lead.
04
Restart the router once
Power-cycle the router once and allow several minutes for sync and authentication. Avoid repeated restarts.
Run these checks once, in order. Repeated restarts can remove evidence without changing an external line fault.
Check more than one device.
If only one device fails, stop treating it as a total outage. If several unrelated devices fail together, continue.
Compare Wi-Fi and Ethernet — then use the copper landline clue if it applies.
A working Ethernet connection proves the broadband service is available and the fault is within Wi-Fi or the device. On FTTC/copper with an active analogue phone service, also note no dial tone, loud hum or persistent crackling; report that voice symptom with the broadband fault. Do not use this clue for Digital Voice/VoIP.
Record router and ONT lights.
Write down exact colours and flash patterns for Internet, Broadband or DSL, PON, LOS and LAN/PORT before restarting.
Check power and cable seating.
Confirm power, WAN, Ethernet and DSL leads are secure. Do not bend, pull or look into the end of a fibre lead.
Restart the router once.
Allow several minutes for broadband sync and authentication to return. Power-cycle an ONT only where the provider’s instructions allow it.
Check provider status and account state.
Use mobile data to check status, run the provider line test and confirm activation, migration or billing has not blocked service.
Broadband down, no dial tone — copper/FTTC clue: if you still have an active analogue phone service, plug a known-good handset into the master socket and listen for a dial tone. This is the same fault pattern users often describe as “broadband down no dial tone”. No dial tone, loud hum or persistent crackling is useful evidence of a physical line or wiring fault; report that symptom alongside the broadband outage. Do not use this test for Digital Voice/VoIP, where the phone depends on the broadband router and may have no dial tone during an internet outage.
Openreach ONT light sequence and UK router fault lights
Light meanings vary by provider and model, so use these as fault-boundary clues and confirm the exact pattern in the provider guide. Each state is written out as text as well as colour so the guide does not rely on colour alone.
Openreach ONT light sequence: PON, LOS and LAN/PORT
Observed state
Likely boundary
What to do next
Red / off — Router has power but Internet/WAN is down
WAN cable, authentication, provider session or external service.
Record the state, check the WAN lead, check provider status and restart the router once.
Flashing — DSL/Broadband is trying to synchronise
Copper or FTTC line is trying to synchronise.
Test the master socket and known-good filter, avoid repeated reboots and report persistent failure.
Red / flashing LOS — optical signal lost
Loss of optical signal or external fibre path fault.
Check that the fibre lead is not loose or sharply bent, then contact the provider if LOS persists.
PON off / flashing — registration problem
Optical registration or service problem.
Wait for the documented start-up period; if it never reaches the normal state, report the light pattern.
LAN/PORT off — Ethernet handoff problem
Ethernet handoff or router WAN lead.
Reseat or replace the Ethernet lead between ONT and router, then check the router WAN port.
Service lights normal — one device fails
Device, DHCP, DNS, VPN or Wi-Fi profile.
Move to device-level troubleshooting instead of reporting an area outage.
Typical Openreach FTTP path
Typical Virgin Media cable path
UK router light quick reference
Exact colours are model-specific. These are useful search clues, not universal rules: match the hub model before changing settings.
BT Smart Hub 2 lights
Solid blue: BT says the hub is connected to broadband.
Flashing orange: the hub is connecting to broadband; give it several minutes.
Solid orange: the hub is working but is not connected to the internet.
Flashing purple: the broadband cable is not connected; on Full Fibre, check the Ethernet lead between the Openreach ONT and hub.
Solid red: BT describes this as a hub problem; restart once and follow BT support if it persists.
Hub 3: green Wi-Fi and Internet lights can appear during startup, and the Internet light can also flash during a software update; the base power light normally settles white.
Hub 4 / Hub 5: these use different single-LED status patterns, so do not apply Hub 3 colour meanings to them.
Hub 5 normal baseline: Virgin Media currently describes the ready state as a steady / solid white light. Some users search for a “solid dim white power light” or “dim warm white” description; match the exact Hub model rather than treating those phrases as a universal fault code.
No service after startup: use Virgin Media's model-specific light guide and run its broadband connection/status test before resetting the Hub.
Sky Broadband Hub / older multi-light hubs: green front lights are the normal online state. If the Internet light is amber or off while power or Wi-Fi remains on, treat it as a broadband-path fault and check the line, WAN/ONT connection and Sky Service Checker.
Sky Max / Gigafast+ Hub: these use a different single-status-light sequence. A slow flashing green state can appear while the hub is authenticated or waiting for internet connectivity; the normal connected state settles to white.
Do not map colours between models: a Sky Max amber/green startup state is not the same thing as an amber Internet light on an older Sky Broadband Hub. Match the exact hub before deciding what failed.
Next: if the hub never reaches its normal online state and Ethernet also fails, run Sky's Service Checker and inspect the Openreach ONT where fitted.
How to use the Openreach master test socket safely
This test bypasses extension wiring and is useful only on a compatible copper/FTTC phone-line master socket. It does not apply to a full-fibre-only ONT connection.
NTE5C master socket test port: bypass extension wiring
On an NTE5C the removable front section clips away to expose the test port; older compatible NTE5 variants may use screws. Do not force a socket that has no customer-removable faceplate.
1. Find the main socket
Use the socket where the external phone line enters the property. A compatible master socket normally has a removable lower faceplate or clip-on front section.
2. Remove only the removable faceplate
Undo the two lower screws if fitted, or release the side clips on compatible newer sockets. Pull the removable section gently forward; do not force or dismantle a socket without a removable faceplate.
3. Connect through a microfilter
Plug a known-good microfilter into the exposed test socket, then connect the router directly to the filter. Disconnect extension devices while testing.
4. Compare the result
If broadband returns at the test socket, the faceplate, filter, extension wiring or attached phone equipment is the likely problem. If it remains down, preserve the result for your provider.
Why this test matters: the hidden test socket connects directly to the incoming line and bypasses internal extension wiring. BT's official test-socket guide documents both screw-front and clip-front master socket types.
Use the panel that matches the access technology rather than applying every reset to every connection.
Full-fibre ONT state errors
The ONT is the handoff between the provider fibre and your router. If broadband is fully offline while Wi-Fi remains active, record the PON, LOS and LAN/PORT lights before restarting equipment.
A failed microfilter, extension socket or faceplate can stop DSL synchronisation. Follow the Openreach master test socket steps above before blaming the external line.
Avoid repeated router reboots because Dynamic Line Management may interpret repeated loss of sync as instability.
Router authentication or firmware failure
A router can have power and Wi-Fi but fail to authenticate or route traffic. One controlled restart may recover the session; repeated restarts are not a substitute for provider diagnosis.
Check the WAN or DSL status page and record any error before factory resetting.
Activation, migration or billing state
A new service, provider switch, missed payment or incomplete activation can leave equipment powered while access remains blocked.
Check the provider account or app over mobile data and ask support to confirm the service state.
4G or 5G home gateways
A mobile gateway can lose service because of SIM, APN, account or radio-network faults. Check the gateway status, mobile-network indicator and provider outage information.
Do not treat NAT type or CGNAT as the cause of a complete outage until the gateway has first restored mobile data service.
Check BT, Sky, Virgin Media or TalkTalk outages and contact support
A provider report is strongest when it shows the whole service is affected and the fault remains beyond Wi-Fi.
Include the equipment evidence
Router and ONT model, exact light colours and flash patterns, whether Ethernet fails, cable checks, restart time and provider status result.
Describe the scope
State whether every device is offline, whether mobile data works, whether the line ever recovers and whether a master-socket or direct-Ethernet test changed the result.
Check the official status page over mobile data: use your provider's own checker before relying on third-party outage reports.
Hi Support,
My broadband connection is completely unavailable.
Affected devices: [ALL / SOME]
Ethernet works: [YES / NO]
Router light state: [DETAILS]
ONT / Fibre Box Light State: [Specify colours or N/A]
Cable and master-socket checks: [DETAILS]
Provider status result: [DETAILS]
Restart performed once at: [TIME]
Please run a line or service test and confirm whether the fault is in the access line, authentication, activation or local network.
Broadband still down? Check automatic compensation
If your provider participates in Ofcom's Automatic Compensation Scheme, a total loss of service that is not fully fixed after two full working days can qualify for automatic compensation. The current 2026 delayed-repair rate is £10.34 for each calendar day the service remains unrepaired, subject to the scheme rules and exclusions.
Quick £10.34/day outage compensation estimate
Enter when the provider recorded the total-loss fault and when service was restored. This lightweight estimator uses weekdays for the two-full-working-day trigger and then counts full calendar days after that.
Important: this is a quick estimate, not an entitlement decision. UK bank holidays, the provider's recorded fault-report time, out-of-hours reporting rules, scheme exclusions and provider participation can change the trigger. Use the full LinkSpeed calculator for a detailed check.
Timing nuance: Ofcom's Code measures from the time the provider receives and can confirm the fault. There is not a universal 4:00pm Friday cut-off. If you report the fault after the usual working hours of the provider's reporting channel on a Friday, the measurement start moves to 9:00am on the next working day — normally Monday, or later if Monday is a bank holiday. Keep the provider's fault reference and recorded report time rather than relying only on when you first noticed the outage.
If the provider records a qualifying total loss of service on Monday during the reporting channel's normal working hours, and Tuesday and Wednesday are both full working days, the initial £10.34 becomes due if the service is still not fully fixed after those two working days. If it then remains unfixed for the whole of Thursday, a further £10.34 is due, taking this example to £20.68. Weekends, bank holidays, exclusions and the exact fault-report timing can affect the working-day count.
Useful evidence: keep the fault-report time, provider reference, restoration date and any missed engineer appointments. Do not assume every provider or every service is covered; check the current Ofcom participant list and conditions.
These answers match the FAQ structured data in the page head.
What should I check first when broadband is down?
Check whether the issue affects one device or every device, then compare Wi-Fi with Ethernet and record the router or ONT service lights before restarting.
Can Wi-Fi make it look as if broadband is down?
Yes. A failed router radio, interference, poor coverage or one device fault can stop wireless access while the broadband line and Ethernet remain available.
What does a red LOS light on a full-fibre ONT mean?
A red or flashing LOS light usually indicates loss of optical signal. Check that the fibre lead is not loose or sharply bent and contact the broadband provider if the light persists.
Should I keep restarting the router during an outage?
No. Restart the router once and allow time for service to return. Repeated restarts can remove useful evidence and may confuse stability monitoring on copper or FTTC lines.
How do I use the Openreach master test socket?
On a compatible copper or FTTC master socket, remove or unclip only the lower removable faceplate, connect a known-good microfilter and router to the hidden test socket, and retest. If service returns, extension wiring, a filter or the faceplate is the likely fault. Do not use this test on full-fibre-only lines or force open a socket without a removable faceplate.
Does a crackling phone line or no dial tone mean the broadband line is faulty?
If broadband is down with no dial tone on a copper or FTTC line that still has an active analogue phone service, the missing dial tone, loud hum or persistent crackling is useful evidence of a physical line or wiring fault. Report the voice symptom as well as the broadband outage. This test does not apply to Digital Voice or other phones that depend on the broadband router.
Can I get automatic compensation when my broadband is down?
If your provider is signed up to Ofcom's Automatic Compensation Scheme, a total loss of service that is not fully fixed after two full working days can qualify for automatic compensation. The 2026 delayed-repair rate is £10.34 for each calendar day the service remains unrepaired, subject to the scheme rules and exclusions.
How is Ofcom broadband compensation calculated after a total loss of service?
Report the fault to a provider that participates in Ofcom's Automatic Compensation Scheme. If the service is not fully fixed after two full working days, an initial £10.34 is due, followed by £10.34 for each full day it remains unfixed after that, subject to the scheme rules and exclusions.
When should I contact my provider?
Contact the provider when every device and Ethernet are offline, router or ONT lights show a service fault, or provider status and line tests indicate a problem outside the home network.
Why is my BT Smart Hub 2 solid orange?
BT describes a solid orange Smart Hub 2 light as the hub working but not connected to the internet. Record the light, check the broadband or ONT connection, use BT's service test and restart the hub once rather than repeatedly resetting it.
What does a slow flashing green light on a Sky Max Hub mean?
A Sky Max Hub uses a different single-light sequence from older Sky hubs. A slow flashing green state can appear while the hub is trying to establish internet connectivity; the normal online state settles to white. If it persists and Ethernet is also offline, check the Openreach ONT where fitted and run Sky's Service Checker.
Why is my Virgin Media Hub 3 flashing green?
On a Hub 3, green Wi-Fi or Internet lights can appear during startup and the Internet light can flash during a software update. If the Hub never returns to its normal state after startup, use Virgin Media's model-specific light guide and connection/status test before factory resetting it.
Print this one-page black-and-white sheet while your connection is working. It has spaces for your ISP account reference, router model, ONT serial number, master-socket location, normal light state, fault reference and restoration time — plus the six checks to run before you call support.
Privacy note: keep the printed sheet somewhere private and do not write Wi-Fi passwords, router admin passwords or account PINs on it.
