This guide is the starting point for the rest of the site. It explains why connections fail, what you are owed when they do, the ways to build a backup, and how to decide. All prices and rules were checked in November 2026 and will change; each figure is numbered and listed under Sources.
What broadband backup is (and what it is not)
Your normal broadband line is the primary connection. A backup is a secondary connection that reaches the internet by a different route. The switch from one to the other is called failover; switching back when the main line recovers is failback. Failover can be manual (you notice the outage and turn on a hotspot) or automatic (a router notices for you and moves every device across).
A few terms come up throughout this site, so here they are once:
- FTTP (fibre to the premises, or "full fibre"): fibre-optic cable runs all the way into your home and ends at a small wall box called an ONT (optical network terminal). Your router plugs into the ONT.
- FTTC (fibre to the cabinet): fibre runs to a green street cabinet and the last stretch to your home uses the old copper phone line.
- Openreach: the BT Group company that builds and maintains the national network used by most providers, including BT, EE, Sky, TalkTalk, Vodafone and Plusnet.
- Ofcom: the UK communications regulator.
It also helps to be clear about what a backup is not:
- It is not better Wi-Fi. Mesh systems and Wi-Fi boosters fix weak signal inside the house. They do nothing when the line itself is dead.
- It is not a battery. A battery (often called a UPS, for uninterruptible power supply) keeps your equipment switched on in a power cut. A backup connection gives that equipment somewhere to send data. For some failures you need both.
- It is not a guarantee. Mobile networks get busy and satellites need a clear view of the sky. A backup turns a dead connection into a slower one, which is usually the point.
Why UK broadband goes down
Outages fall into four families, and the family matters because each backup option covers a different set.
1. Faults on your line. A cable is cut by roadworks, a street cabinet fails, water gets into a joint. These affect you and perhaps your neighbours, and they are fixed by an engineer, so they can last days. In a Uswitch survey published in November 2025, people who had suffered damage to cables outside their property reported an average of 33.4 hours offline for that cause 4.
2. Provider outages. Something breaks inside your provider's network, such as routing, authentication or a regional hub. Thousands of customers lose service at once and the fix is usually remote. The same survey put the average at 11.2 hours for those affected 4.
3. Your own equipment. Routers fail, power supplies die, firmware updates go wrong. Nothing is wrong with the line, but you are offline all the same.
4. Power cuts. No electricity means no router, and in a wider cut it can mean no street cabinet or mobile mast either. In Uswitch's October 2026 survey, power cuts were named as the top cause of lost broadband, and the company estimated that 26.7 million people had lost their connection at some point in the previous year 3. The 2025 survey put the average power-cut outage at 14.2 hours for those affected 4.
Treat those numbers with some care. They come from surveys of 2,000 adults commissioned by a comparison site, and they rely on people remembering how long they were offline 34. They are still the best public indication of what households experience.
Repair times explain why a line fault hurts. Openreach offers providers different "service maintenance levels". At level 1, the target is to fix a fault by 23:59 two working days after it is reported, counting Monday to Friday. At level 2 the target is 23:59 on the next working day, counting Monday to Saturday 14. Under level 1, a fault you report on a Friday can run until Tuesday night and still be on target. Ask your provider which level your line has.
What an outage costs you, and what Ofcom compensation actually pays
Ofcom runs an automatic compensation scheme that many of the largest providers have joined. From 1 April 2026 the amounts are 1:
| Problem | Compensation | When it applies |
|---|---|---|
| Delayed repair after loss of service | £10.34 per calendar day | Service has stopped and is not fully fixed after two full working days |
| Missed engineer appointment | £32.31 per appointment | Engineer does not arrive, or cancels with less than 24 hours' notice |
| Delayed start of a new service | £6.46 per calendar day | Provider misses the promised start date |
The members are BT, EE, Hyperoptic, Plusnet, Sky (including NOW Broadband), TalkTalk, Utility Warehouse, Virgin Media, Vodafone and Zen Internet 1. If your provider is not on that list, none of this is automatic.
Three things limit how useful the scheme is when you need to work:
- Nothing is paid for the first two working days. A total outage that is fixed inside that window earns nothing 1.
- It covers total loss of service on residential lines. The scheme is described as covering residential fixed broadband and landline products, and it excludes faults caused by equipment or activity inside your home 1. Slow speeds and intermittent drops are a separate complaint.
- The sums are small. Take a fault reported on a Monday morning and fixed the following Monday morning. The two working days run out at the end of Wednesday, leaving four full calendar days (Thursday to Sunday) at £10.34: about £41. Your provider's own counting of days may differ slightly.
In total the scheme paid out just over £63 million in 2024, across roughly a million payments 2. Yet in the October 2026 Uswitch survey only 16% of people hit by an outage said they had received compensation, and 57% did not know they could ask 3.
Now do your own side of the sum. If you are self-employed and bill by the day, or you are an employee who has to take leave or travel to an office when the line is down, a single lost day usually outweighs the compensation for a week. That gap, not the compensation, is the number to compare with the price of a backup.
The ways to back up a connection
There are four paid routes, plus the free one most people already own.
| Option | How it works | Indicative cost (November 2026) | Switch-over | Detailed guide |
|---|---|---|---|---|
| Phone hotspot | You turn on tethering and connect your laptop | No extra cost; uses your mobile data | Manual | 4G and 5G backup broadband |
| Provider 4G add-on | A small device or dongle from your broadband provider connects to its mobile network when the line drops | EE: £10 a month 10. Vodafone: included with Pro plans, 100 GB a month 11 | Automatic | ISP backup vs DIY vs satellite |
| Your own 4G/5G router and SIM | A router with a SIM slot and a failover port sits on your network and takes over | Router from about £89 15; rolling unlimited-data SIMs listed from about £16 to £18 a month 13 | Automatic, if the router supports it | 4G and 5G backup broadband and the setup guide |
| Second fixed line | A second broadband service on a physically different network, joined by a dual-WAN router | The price of a second broadband package | Automatic | Business broadband backup |
| Satellite | A dish talks to low-orbit satellites, bypassing local cables and masts | Starlink residential plans from £40 a month; a low-speed Standby Mode costs £9 a month 1912 | Depends on setup | ISP backup vs DIY vs satellite |
Which failures does each one survive? This is the table to keep in mind when you choose.
| Failure | Phone hotspot | Mobile backup (provider or DIY) | Second fixed line | Satellite |
|---|---|---|---|---|
| Fault on your line | Yes | Yes | Yes, if it uses a different physical network | Yes |
| Provider-wide outage | Yes | Yes | Yes, if it is a different provider and network | Yes |
| Your router fails | Yes | Only if the backup has its own router or Wi-Fi | Only with a separate router | Yes, it has its own router |
| Power cut at your home only | Yes, while the phone has charge | Only with a battery for your equipment | Only with a battery | Only with a battery |
| Wide-area power cut | Depends on whether the mast stays powered | Depends on the mast, and needs a battery at home | Depends on street cabinets, and needs a battery | Needs a battery at home; does not rely on local masts |
Mobile is the default backup for a practical reason: each UK operator's 4G network reaches at least 99% of premises outdoors 5, so most homes have at least one usable network.
Two rules fall out of that table. First, the backup should use a different route from the main line: a second service that runs through the same street cabinet or the same provider's core network can fail at the same moment. Second, anything plugged into the mains needs a battery behind it before it counts as cover for a power cut.
Power cuts and the landline switch-off: the gap most backups miss
The old analogue phone network, known as the PSTN (public switched telephone network), is being retired by 31 January 2027 6. Landlines are moving to digital services that run over your broadband connection 7. For most homes the change is a new socket on the back of the router. For resilience it changes two things.
Your landline now fails when your broadband fails. A line fault used to leave the phone working. With a digital landline, phone and broadband go down together. Whether a broadband backup also carries your landline depends on the provider and the product, so ask before you rely on it.
Your landline now fails in a power cut. Analogue phones drew power from the exchange. Digital landlines need mains electricity at home and will not work in a power cut unless there is a battery 7. If you depend on your landline, your provider must make sure you can reach the emergency services during a power cut; that solution must last at least one hour, and some providers offer units that run for up to seven hours 7. One battery unit adopted by several UK providers in 2025 was specified to run a 25-watt router for seven hours or a 55-watt router for four 16.
The usual advice is that a mobile phone covers the gap. That holds when the cut is limited to your home or street. In a wider cut it is less certain. Ofcom revised its network resilience guidance on 16 June 2026 to spell out what it expects from mobile operators on backup power at mast sites, but it did not set a fixed number of hours; for street cabinets on fixed networks it treats about four hours as good practice 89.
What this means in practice:
- Put the fibre box (ONT) and the router on a battery if staying online in a power cut matters to you. Both need power, and the backup device does too.
- Keep a charged power bank for your phone. It is the cheapest resilience you can buy.
- If anyone at home relies on a telecare alarm or the landline for emergencies, tell your provider. You may be entitled to a free battery unit 7.
- Do not expect a hard cut-off on 31 January. Openreach has described temporary measures for lines that have not moved in time, but they are a stopgap with limits, not a reason to wait 17.
Do you need a backup? A five-question check
Work through these in order. Stop when the answer is clear.
1. What does an hour offline cost you? Put a number on it. For an employee with an office to go to, it may be an inconvenience. For a freelancer on client calls, a therapist running video sessions or anyone trading online, it is lost income. If the honest answer is "very little", you do not need to spend money.
2. How often are you offline, and for how long? Look at your own record, not national surveys. Many routers keep a log of disconnections, and your provider's app often shows fault history. Two short blips a year suggest a different answer from a line that fails every time it rains.
3. Is your phone enough? Check three things at your desk, not in the garden: signal strength, your monthly data allowance, and whether your plan allows tethering. If all three are good and only one or two devices need to stay online, a hotspot is a legitimate backup. Its weakness is that it is manual and it leaves with you when you go out.
4. Is power the real problem? If your outages coincide with power cuts, a second connection will not help until the equipment has a battery. Solve power first.
5. Does anything need to stay online when you are not there? Smart heating, cameras, a home server, a partner or lodger working upstairs, a card machine. These are the cases where automatic failover earns its keep, because nobody is around to switch on a hotspot.
If you reached question 5 and answered yes, or the cost in question 1 is more than a few pounds an hour, a paid automatic backup is easy to justify. If you stopped at question 3, save your money.
What it costs: realistic monthly budgets
Prices checked November 2026. Hardware prices move weekly and mobile deals change often, so treat these as a guide to the order of magnitude.
| Budget | What you get | Notes |
|---|---|---|
| £0 | Phone hotspot | Manual. Uses your existing mobile allowance. |
| About £10 a month | A provider add-on such as EE Connectivity Backup at £10 a month 10 | Automatic. Only available from certain providers and tied to their router. |
| £13 to £18 a month, plus hardware | A second, always-on mobile connection: for example Three's unlimited 5G Home Broadband, advertised at £13 a month on a 24-month contract in November 2026 18, or a rolling unlimited-data SIM at about £16 to £18 13 in a 4G router costing from about £89 15 | Automatic with the right router. Works with any broadband provider. Annual price rises apply to many contracts. |
| £40 a month and up, plus a dish | Starlink Residential from £40 a month 19 | Independent of local cables and masts. Hard to justify as a backup unless mobile signal is poor. |
| The price of a second line | A second fixed broadband service | Mostly a business choice; see the business guide. |
Remember the hidden line in every budget: a battery, if power cuts are part of your risk.
Where to go next
- You want to understand mobile backup properly (routers, SIMs, data, signal): read 4G and 5G backup broadband.
- You run a business and need to think about phones, card payments and service agreements: read Business broadband backup.
- You have decided and want instructions: follow How to set up automatic broadband failover at home.
- You are choosing between a provider add-on, a DIY kit and satellite: read ISP backup vs DIY vs satellite.
FAQ
What is broadband backup?
It is a second internet connection that takes over when your main broadband fails. In UK homes it is usually a 4G or 5G mobile connection, supplied by your broadband provider as an add-on or built from your own router and data SIM. The switch can be manual or automatic.
Does broadband backup work in a power cut?
Only if your equipment has power. A mobile backup device, your router and, on full fibre, the ONT all need electricity. With a battery behind them the backup can work in a local power cut. In a wide-area cut it also depends on whether the local mobile mast stays powered, and Ofcom's guidance does not set a minimum number of hours for that 89.
Can I just use my phone as a hotspot?
Yes, and for many people it is enough. It costs nothing extra, provided your mobile plan allows tethering and has enough data. The drawbacks are that you must switch it on yourself, it drains the phone, it serves only the devices you connect to it, and it stops when you leave the house.
Will I get compensation if my broadband goes down?
Which UK broadband providers offer a backup?
EE sells Connectivity Backup as a £10-a-month add-on 10 and Vodafone includes a 4G backup dongle with its Pro broadband plans 11. The full comparison, including BT and the providers that do not offer one to households, is in ISP backup vs DIY vs satellite.
Will my landline work on a backup connection?
Not necessarily. Digital landlines run over broadband 7, and whether calls continue over a mobile backup depends on the provider and the product. Ask your provider, and keep a charged mobile phone as your fallback for emergency calls.
Is satellite a sensible backup?
For most homes with a usable mobile signal, no: it costs more and needs a dish with a clear view of the sky. It makes sense where mobile coverage is poor, or where you want a connection that does not depend on local cables or masts. Starlink's residential plans start at £40 a month and its low-speed Standby Mode costs £9 a month 1912.
Sources
Checked 13 November 2026.
- Ofcom, "Automatic compensation: what you need to know" (rates from 1 April 2026): ofcom.org.uk
- ISPreview, "Ofcom Raise UK Consumer Compensation Payments for Broadband ISP Woes", 4 April 2026: ispreview.co.uk
- ISPreview, "Survey claims power cuts are top cause as broadband outages hit half of UK" (Uswitch/Opinium survey, 29 September to 2 October 2026), 8 October 2026: ispreview.co.uk
- Uswitch, "22.4m Brits hit by broadband outages in the last year", November 2025: uswitch.com
- Ofcom, "Connected Nations update: Spring 2026", 13 May 2026: ofcom.org.uk
- Openreach, "Time for a 'big switch-up' as PSTN switch-off looms", 5 February 2026: openreach.com
- Ofcom, "Future of landline calls": ofcom.org.uk
- Ofcom, "Statement: Network and Service Resilience Guidance" (last updated 16 June 2026): ofcom.org.uk
- Osborne Clarke, "Telecoms: UK Regulatory Outlook July 2026", 29 July 2026: osborneclarke.com
- EE, "EE Home Price Guide" (add-on prices, April 2026): ee.co.uk
- Vodafone, "Pro Broadband" (4G Broadband Back-up terms): vodafone.co.uk
- ISPreview, "Starlink Unexpectedly Hikes UK and Global LEO Satellite Broadband Prices", 17 May 2026: ispreview.co.uk
- Ken's Tech Tips, "Unlimited data SIM plans" (listings viewed November 2026): kenstechtips.com
- Openreach, "Our performance FAQs" (service maintenance levels): openreach.com
- PriceSpy UK, TP-Link 4G/5G router listings (viewed November 2026): pricespy.co.uk
- ISPreview, "Broadband ISPs Vodafone, BT, KCOM and Zen Internet Prep New UK Battery Backup", 14 March 2025: ispreview.co.uk
- ISPreview, "Openreach confirm post-January 2027 measures for UK analogue phone switch-off", 24 September 2026: ispreview.co.uk
- ISPreview, "Three UK cuts unlimited 5G Home Broadband plan price to just £13pm", 6 November 2026: ispreview.co.uk
- Broadband.co.uk, "Starlink broadband deals" (prices checked 2 November 2026): broadband.co.uk
General information for UK households and small businesses, not legal, financial or technical advice. Facts checked on 13 November 2026; prices, coverage and rules change, so confirm the details with a provider before you buy.