Backup Internet for When Your Broadband Goes Down
Broadband fails for hours, not minutes — a cut cable in the street, a router that won’t come back, an exchange fault with no fix time. A FlexiFone SIM in a phone or a spare router puts you back online in under a minute, on whichever of the four UK networks has signal at your address. No engineer visit, no second broadband line.
- All four UK networks, switching automatically
- Roam like home in 170+ countries (25GB a month abroad)
- Allow or block networks from your portal
- eSIM free, or a triple-cut physical SIM for £3.50
For failover you're buying readiness, not volume. The SIM stays live with an allowance waiting, and 30GB covers a full day of a whole household — TVs, laptops, everyone's phones — with room to spare if the line stays down overnight. A prepaid SIM left in a drawer expires. This one doesn't.
Explore Plans →Only need to keep one person working? The 10GB plan is £65 a year — £5.42 a month. Enough for a laptop and a phone through an outage, but not a house that streams.
Why a Multi-Network SIM Is the Right Backup
A backup connection has one job: to work on the day the main one doesn’t. That rules out anything sharing the same infrastructure — and anything tied to a single mobile network.
Your number goes with you
A backup on one mobile network is still a single point of failure. FlexiFone holds EE, O2, Vodafone and Three, so the odds of having no usable signal at your address drop to almost nothing.
It takes over on its own
Nothing to configure at the moment it matters. The SIM sits in as a second line, and when the broadband stops your phone is already on mobile data — then hotspot the laptop as normal.
Independent of your line entirely
A mesh node, a powerline adapter or a second router all fail with the line. Mobile data doesn’t share the cable, the cabinet or the exchange, so the two can’t fail together.
Almost nothing to keep ready
£3.75 a month for a connection you might use twice a year is the whole argument. A second broadband line costs many times that and can be taken out by the same roadworks.
When a Backup Connection Earns Its Keep
Four situations, and what actually happens in each.
| Scenario | The problem | What FlexiFone does |
|---|---|---|
| Working from home on an outage day | A full day of calls and shared documents, and the fault has no fix time. | Hotspot the laptop from your phone and carry on. Video calls, email and cloud files all work on mobile data. |
| A shop or salon taking card payments | The terminal is offline, so you're turning away paying customers. | Move the terminal onto the FlexiFone SIM or your hotspot and keep taking payments until the line is back. |
| A router with an empty SIM slot | Your 4G-capable router has a SIM tray and nothing to put in it. | A triple-cut physical SIM for £3.50 fits most routers and MiFi units, so failover happens without anyone noticing. |
| An outage at the worst moment | A deadline, an interview or an exam, and no time to wait for support. | The line is already active with an allowance waiting, so there's nothing to buy or activate while the clock runs. |
Scroll the table sideways to see all three columns →
Everything You Need to Know About Backup Internet
Planning for more than outages? Check out our dedicated guides for, remote work and international travel.
See all plans →Roughly 1–3GB for a normal day of email, documents and messaging, with video calls the main variable — about 0.5–1.5GB an hour depending on quality. 5GB a month covers a couple of outage days comfortably. If the SIM is your everyday connection rather than a backup, take the 10GB plan.
No, though it helps. Many 4G and 5G routers have a SIM slot that takes over automatically when the broadband line drops — put the physical SIM in there and failover is invisible. Without one, tethering from your phone does the same job with one tap.
You can, and on the day it works you’ll be glad of it. Two things go wrong: most contracts restrict or throttle tethering, and your phone is on one network — if that network is weak at your address, your backup fails at the same time as your broadband. A multi-network SIM removes both problems.
Yes. The plan refreshes every 30 days whether you use it or not, so the SIM is live and has an allowance waiting whenever you need it. This is the practical reason a subscription beats a prepaid SIM for backup — prepaid pots expire, usually just before you need them.
Yes. Tethering is unrestricted on every plan, so one phone can keep a household or a small team going. Watch the allowance — a few people streaming will get through 5GB faster than a few people working.
FlexiFone for every situation
Same SIM, different problem
One product, several reasons to want it. These are the other three worth reading.
Get a backup line before you need one
£45 for the year, live in minutes on eSIM. Or tell us what your setup is and we'll say honestly whether you need it.
