The short answer
Mobile broadband means getting online through the mobile network with a device you can carry: a USB dongle, a pocket MiFi or your phone's hotspot. It moves with you and needs no phone line or engineer.
Its weakness is that everything rides on one mobile signal and one data plan. Vodafone says its mobile broadband speeds vary with coverage and network conditions and can change as you move around. The networks draw the line in the same place: Vodafone points people who want internet at home to its separate 5G Broadband, and Three sends anyone who needs an indoor home connection to its Home Broadband rather than its MiFi.
So portable kit suits travel, short stays, a single light user, a gap between connections or a backup. A household that stays put is usually better served by a fixed line or a plug-in 4G or 5G home hub. For the hub option, our guide on whether 4G or 5G home broadband can replace a fixed line goes into it in depth.
What counts as mobile broadband
There are four common ways to get online over the mobile network. All need a mobile data plan and signal; none uses a phone line.
- USB dongle. A small modem that plugs into a computer's USB port and connects that one computer.
- Pocket MiFi. A battery-powered portable router that makes its own Wi-Fi network for several devices. Three says MiFi, mobile Wi-Fi and portable Wi-Fi all mean the same thing; Vodafone calls its devices Mobile Hotspots.
- Phone hotspot. Your smartphone shares its mobile data with other devices, often called tethering.
- Data-only SIM in a tablet or laptop. A SIM with data but no calls, used in a tablet or laptop that has a SIM slot or built-in mobile (cellular) connectivity, or in a dongle or MiFi. Three says most tablets have a slot for a data SIM.
These are different from 4G and 5G home broadband. Three describes its home hub as a router that plugs in at home and turns the mobile signal into Wi-Fi, with no engineer visit, and EE says its home router plans are for indoor use in a fixed location.
USB dongles: one computer, no charging
Three describes a data dongle as roughly the size of a USB stick. It plugs into a USB port on a laptop or computer and takes its power from that computer, so it never needs charging or a plug socket, and it connects to 4G or 5G in the same way a smartphone does.
The trade-off is that a dongle only connects the device it's plugged into, and it only works with devices that have a USB port. Before buying one, check that its plug fits the ports on your computer.
Not every network sells one. When we checked in October 2026, Vodafone listed a 4G Mobile Dongle, while EE's and Three's mobile broadband pages listed portable Wi-Fi devices but no separate USB dongle.
Who a dongle suits: one person with one computer who wants the simplest setup, for example someone working on a laptop on trains or in hotel rooms.
Pocket MiFi: a small router that runs on a battery
A MiFi is a battery-powered mobile broadband router. It creates a Wi-Fi hotspot that phones, tablets and laptops can join at the same time. Three says its MiFi is about the size of many popular smartphones and can keep you connected for up to six hours on one charge, so plan for charging on a long day out. A MiFi bought from Three comes with its data SIM included.
How many devices can connect
When we checked in October 2026, the networks' current pocket devices had generous limits:
- Three lists both its 5G MiFi and its 4G MiFi at up to 32 connected devices.
- Vodafone lists its 5G and 4G Mobile Hotspots at up to 32 connected devices.
- EE's product listing for its portable 5G WiFi device says it connects over 100 devices.
Older devices can have lower limits, so check the exact model you're offered. Treat the figure as a maximum, not a promise of how well they'll all run: every device shares the same mobile connection and data allowance. EE's small print for its home routers makes the point that the more devices connected at the same time, the slower the connection.
Getting the best signal
Because a MiFi isn't tied to a socket, you can move it to wherever the signal is strongest. Three's support page suggests putting its mobile Wi-Fi by a window, and EE gives the same advice for its home routers, recommending a spot on or near a window sill. If you'll use it in the same building a lot, try a few spots and run our broadband speed test on a connected device in each one, at different times of day.
4G or 5G?
Vodafone says using 5G needs three things together: a 5G-enabled device, a 5G plan and 5G coverage where you are. So a 4G-only device won't use 5G even on a 5G plan: Vodafone's own comparison shows only its 5G Mobile Hotspot as 5G-ready. EE says 5G uses both the 5G and 4G networks, and that where you're not covered by 5G a 4G plan or device could be worth considering.
Using your phone as a hotspot
If you already have a smartphone with a decent data allowance, turning on its hotspot shares that mobile data with other devices, with no extra kit to buy.
- iPhone and iPad. Apple calls it Personal Hotspot. It works on iPhones and on iPads with mobile connectivity (Wi-Fi + Cellular models), and needs a network provider that supports it. Other devices can join by Wi-Fi, USB cable or Bluetooth. Apple says how many devices can join at once depends on your network provider and iPhone model.
- Android. Google says an Android phone's Wi-Fi hotspot can share with up to 10 other devices, and that you can also tether by USB or Bluetooth. One catch: Google says Macs can't tether to an Android phone over USB.
Check your plan before you rely on it
Apple says additional fees may apply to Personal Hotspot, and Google says some mobile operators limit or charge extra for tethering and recommends checking with your operator. We couldn't verify each UK network's current tethering terms, so don't assume your whole allowance can be shared. Check your plan's terms, or ask your network, whether tethering is included, whether it has its own data limit and whether it costs extra.
Battery, data and features that may not work
- Battery. Google's advice is to plug in your phone and the connected devices while tethering, turn tethering off when you've finished, and use automatic hotspot shut-off if your phone has it. While your phone is everyone's router, a flat battery takes your calls and your internet with it.
- Data. Apple advises turning Personal Hotspot off when you don't need it, to avoid unnecessary data charges. A laptop left connected may also sync files or download updates in the background.
- Wi-Fi-only features. Apple says some features that need Wi-Fi, such as iCloud backups or uploading to iCloud Photos, may not work over Personal Hotspot.
Data allowances, contracts and costs to check
Terms for portable mobile broadband vary by network:
- Three offers 1-month, 12-month and 24-month plans, plus Pay As You Go data SIMs with no commitment. It says unlimited data is one of its Pay Monthly plans, which can be fixed-term or rolling monthly.
- Vodafone offers 30-day, 12-month and 24-month plans, and its devices need a Vodafone SIM, either a physical card or an eSIM (a digital SIM built into the device).
- EE describes its portable Wi-Fi devices as being on flexible contracts.
A short plan suits a temporary need; a 12- or 24-month term only makes sense if you're sure you'll keep using the device. Check the price rises too. Since 17 January 2025, Ofcom's rules require providers to tell you in pounds and pence, before you sign up, exactly how much your monthly price will rise during the contract and when. Vodafone's mobile broadband listings show their April rises in pounds, and Three says Mobile Broadband plans taken on or after 9 November 2025 go up by a fixed amount each 1 April.
"Unlimited" usually has conditions
Read the fair-use terms on any unlimited plan. For example, EE's unlimited home router plans are for personal, non-commercial use, and EE treats use above 1,000GB a month as non-personal, with the right to slow its traffic at busy times or move the customer to a business plan. That's a home plan, not a portable one, so find the equivalent wording for the plan you're buying. If you're not sure how much data you get through, our guide to how much data home broadband uses explains how to estimate it.
Questions to ask before you sign up
- How much data is included each month, and what happens when it runs out: does the connection stop, slow down or cost extra?
- Is the plan Pay As You Go, rolling monthly or a fixed term, and what does it cost to leave early?
- Is the device included, and is it 4G or 5G?
- How many devices can it connect at once?
- Is the plan for personal use only, and are there fair-use limits on "unlimited" data?
- Can you use the plan abroad, and in which countries?
Check coverage where you'll actually use it
Coverage decides whether mobile broadband works for you, and it can vary between networks at the same spot.
Ofcom's broadband and mobile checker works by postcode and also links to mobile coverage. Ofcom shows predictions, not guarantees: it says actual availability may differ from what the checker shows. Check the networks' own coverage checkers too, for every place you'll use the device. A dongle or MiFi works on the network of its SIM, so check that network's coverage, and make sure the device itself supports 5G if you're paying for a 5G plan.
What the national figures say
- Ofcom's Connected Nations 2025 report, as reported by ISPreview in November 2025, put 4G coverage at 89% to 90% of the UK's landmass across all operators, and 96% from at least one. It found 5G equipment on 48% of mobile sites in urban areas but only 20% of sites in rural areas.
- Ofcom's spring 2026 update, using January 2026 data and also reported by ISPreview, put individual operators' outdoor 5G coverage at between 76% and 94% of premises, and outdoor 5G from all operators at 64%. ISPreview's table of the same data shows 5G reaching 73% of the UK's land area from at least one operator, but 48% of Scotland's.
- The government says the Shared Rural Network, a programme to improve rural 4G, met its main target a year early: by June 2025, over 95% of the UK was within range of a 4G signal.
Two practical points follow. First, the 5G figures are for outdoor coverage, so treat indoor use as a separate question and test it. Second, far fewer rural mobile sites have 5G equipment, so in the countryside a 4G device on the strongest local network may be the realistic choice. If indoor signal is the problem, our guide to which mobile signal boosters are legal in the UK explains what you can and can't use, and our guide to rural broadband options compares the alternatives.
Taking mobile broadband abroad
- Vodafone says using your home data plan in its Zone A is included in all its Pay Monthly plans, while other destinations are charged depending on your plan. Its Pay as you go terms differ: data is for the UK and Zone A only unless you buy a roaming extra.
- Three says to set up international roaming on your account, through My3, before you go.
- GOV.UK says surcharge-free roaming in EU and EEA countries is no longer guaranteed, so check your operator's policy before travelling.
- GOV.UK also says UK law keeps a spending limit on mobile data roaming of £45 per monthly billing period: you can't keep using mobile data abroad beyond it unless you actively choose to keep spending. You should get alerts at 80% and 100% of your data use while roaming.
- Near the Northern Ireland border, operators must tell customers how to avoid roaming by accident and take reasonable steps to protect them from those charges.
These rules are written about mobile roaming generally, so ask your network how the limit and alerts work on a data-only SIM or MiFi plan. The full rules are on GOV.UK's page on using your mobile in EU and EEA countries.
When mobile broadband is a sensible choice
Three describes mobile broadband as ideal for travel and remote or hybrid working. Typical situations where it fits:
- Working on the move. A laptop user who commutes or travels for work.
- Short stays. A holiday let, a placement or time between student lets, where rolling monthly or Pay As You Go plans avoid a long contract. Our guide to broadband for students covers the house-share side of that.
- A gap while you move. If your new home's line isn't ready, a hotspot or MiFi can tide you over. Our guide to broadband when moving home explains what to do about the main contract and the timing.
- A backup. If you work from home, a mobile connection can keep you going if your fixed line fails. Some fixed broadband plans include this: Vodafone's Pro 2 and Pro 3 plans come with a 4G back-up dongle with 100GB of monthly data that takes over if the line goes down (see Vodafone broadband deals). Our guide to a backup broadband connection compares the options.
- One light user with strong signal. Someone living alone who mostly browses and emails may get by on a MiFi, if the data allowance is enough.
When a home connection usually works better
If several people are online at once, streaming, gaming or on video calls, a home connection is usually the better fit. It doesn't run on a battery, and fixed lines don't depend on mobile signal. Fixed options have also spread a long way: Ofcom data for January 2026, reported by ISPreview, put full fibre within reach of 82% of UK homes and gigabit-capable broadband at 89% of UK homes.
If you'd still rather use the mobile network at home, for example because you can't get a good fixed line or don't want a long commitment, a plug-in 4G or 5G home hub is the step up from a MiFi, on mains power and built for a whole household. When we checked in October 2026:
- Three said its Home Broadband hub connects up to 32 devices and its Pay Monthly Home Broadband plans come with a 30-day money-back guarantee. Three says its 5G hub can move house with you if the new address has coverage. See our page on Three broadband deals.
- Vodafone offered its 5G Broadband on rolling 1-month, 12-month or 24-month plans. Unlike its portable range, Vodafone says it can guarantee coverage and speeds for this home service based on your postcode.
- EE's small print for its Smart 4G and 5G hubs listed an 18-month minimum term or a 30-day contract, and EE says the plug-in setup, with no engineer, is ideal for renters or anyone moving home. See EE broadband deals.
To see what's available, enter your postcode in the comparison on our broadband-only deals page. It lists home broadband deals at your address, including 4G and 5G home broadband where it's available there. Portable dongle and MiFi plans are sold by the networks themselves, so check their sites for those. You can also browse broadband deals by area for your town.
Side-by-side comparison
Our summary of the information above; limits and terms vary by product.
Option | Power | What it connects | Portable? | Usually suits |
|---|---|---|---|---|
USB dongle | From the computer's USB port; no charging | Only the computer it's plugged into | Yes | One laptop user on the move |
Pocket MiFi | Built-in battery; needs charging | Several devices over Wi-Fi (Three and Vodafone list up to 32) | Yes | Travel, short stays, small groups |
Phone hotspot | Phone battery | Other devices by Wi-Fi, USB or Bluetooth (limit depends on phone and network) | Yes | Occasional, short sessions |
Plug-in 4G/5G home hub | Mains power | A whole home over Wi-Fi | Plugged in at one address; can move with you | Homes without a good fixed line, renters, short stays |
Fixed-line broadband | Mains power | A whole home over Wi-Fi and cable | No | Households that stay put and share the connection |
Mobile broadband FAQs
What's the difference between a dongle and a MiFi?
A dongle plugs into a computer's USB port, takes power from it and connects only that computer. A MiFi is a small battery-powered router that creates its own Wi-Fi network, so phones, tablets and laptops can share it at once. A MiFi needs charging but suits anyone with several devices.
Can I use my phone's hotspot instead of home broadband?
For short spells, yes. iPhones and Android phones can share their mobile data by Wi-Fi, USB or Bluetooth. As an everyday household connection it's harder going: it drains your phone's battery, uses your phone's data allowance, and some networks limit or charge extra for tethering. For daily use, a MiFi, home hub or fixed line usually works better.
Do I need a phone line for mobile broadband?
No. Dongles, MiFi devices and phone hotspots all use a mobile data plan and the mobile network, not a phone line, and there's no engineer visit. All you need is a SIM with data and good enough signal where you'll use it. Plug-in 4G and 5G home hubs work the same way: Three says its broadband never needs a landline.
How many devices can connect to a mobile Wi-Fi device?
It depends on the product. When we checked in October 2026, Three listed its 5G and 4G MiFi at up to 32 devices and Vodafone listed its 5G and 4G Mobile Hotspots at up to 32. That's the most that can connect, not how many will run well, because they all share one mobile connection and one data allowance. Check the exact device's specification.
Can I use mobile broadband abroad?
Often, but check before you travel. Vodafone says roaming in its Zone A is included in all its Pay Monthly plans, while other destinations cost extra. GOV.UK says free EU roaming is no longer guaranteed, and UK law limits mobile data roaming spending to £45 per monthly billing period unless you choose to carry on spending.
How do I check mobile coverage at my address?
Enter your postcode in Ofcom's broadband and mobile checker, which links to mobile coverage results, then check the networks' own coverage checkers. Treat all of them as predictions: Ofcom says actual availability may differ. Test indoors if you can, because the published 5G figures are for outdoor coverage.
Is mobile broadband good enough for working from home?
It can be for one person with strong signal and enough data, especially as a stopgap or a backup. Vodafone says its mobile broadband speeds vary with coverage and network conditions, and every device you connect shares the same connection. If you work from home every day, a fixed line or plug-in home hub, with mobile as a backup, is usually more dependable. Our guide to broadband for working from home covers what to look for.
