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A Mobile Wi-Fi router, or MiFi for short, is a portable gadget that lets you share an internet connection to other devices from a SIM card with a mobile data plan. Dual Band Wi Fi Router
You might wonder why you need one at all when you could use your phone’s portable hotspot (or tethering) feature to create a Wi-Fi network for other devices to connect, but if you’re travelling in another country you might prefer to keep your usual SIM in your phone and pop a local SIM card into a mobile Wi-Fi router to share its data with all your Wi-Fi devices, including a laptop, tablet and even a Fire Stick you might take with you.
If you need a mobile Wi-Fi hotspot regularly, a MiFi router can be the preferred solution because they won’t drain your smartphone’s battery, there’s no fiddling around with swapping SIM cards, and you won’t need to leave your phone with whomever is sharing its internet connection. They can also be used with data-only SIMs (those that do not offer calls and texts), which can make it cheaper to get online.
And in case you’re wondering, the difference between a mobile Wi-Fi router and a mobile data dongle is that a router does not physically connect to your device, and it can share a mobile data connection with more than one device. You could plug a dongle into your laptop or PC, but the advantage of the MiFi routers below is that they provide an internet connection to multiple devices at the same time.
TP-Link’s M7350 is a solid 4G mobile router that has the big benefit of being network-unlocked. That means although you’ll pay in full upfront, you can choose any data deal from any UK network operator, and you aren’t tied to a contract.
The TP-Link supports all three UK 4G LTE bands, with up to 150Mbps download speeds and 50Mbps uploads. It can create a wireless network for up to 10 devices, and supports a microSD card for shared storage and has an LCD that tells you the signal strength, how many devices are connected, how much data you have used of your total limit, plus the remaining battery capacity.
You can also use the LCD to cycle through a menu that caters to such options as toggling on or off data roaming, switching between 2.4- and 5GHz output, and choosing between 4G, 3G or a mixture of both.
A final option displays a QR code that takes you directly to Google Play or the App Store to download the tpMiFi app, which lets you manage users, alter the range, share files and read text messages.
The TP-Link’s 2550mAh battery should be good for up to 10 hours of 4G connectivity, but lasts days on standby.
Available on contract through Three, the Huawei E5576-320 offers such great value that you’d be crazy not to simply buy the network-unlocked version outright.
This is a 4G mobile router that lets you connect up to 10 devices, with its 1500mAh battery offering a standby time of up to 350 hours and working time of up to 6 hours.
It’s small, compact and easily portable – but, more importantly, it’s functional, with up to 150Mbps download speeds and 50Mbps uploads.
There are no fancy extra features, with this affordable mobile router from Huawei instead concentrating on one primary task: getting your mobile devices online wherever you are.
TP-Link’s M7220 is a no-frills mobile Wi-Fi router that supports 4G FDD-LTE/TDD-LTE and 3G networks. It’s SIM-unlocked, so you simply unclip the back panel, pop in your SIM, and switch it on. It’s that easy to set up.
The 2,000mAh internal battery can last up to 8 hours in use, but significantly longer on standby, and you can share its 2.4GHz mobile Wi-Fi connection with up to 10 devices.
This is a rather plasticky device, and we were worried about snapping the rear panel when trying to prise it off to insert the SIM, but it’s tougher than it looks. The Wi-Fi network name and password are hidden under this panel, however, so you might prefer to make a note of it than to have to keep pulling on and off the panel every time you want to share the network.
The display doesn’t give you any stats about how much data you’ve used, but three status lights keep things super-simple: you can see how much battery remains, whether you’re connected to the internet and if it is sharing a Wi-Fi network.
Should you want to access more settings you can use the free mobile app or connect to the router via its login page on a browser, but otherwise the TP-Link keeps things simple for those who just want to turn it on and get online.
The TP-Link M7450 is a newer, more advanced version of the M7350, but it’s also more expensive and we think the older model currently offers better value.
Like the M7350, it’s sold unlocked and should work with any major network, either in the UK or abroad. It supports Cat6 LTE, with 300Mbps downloads (double the M7350) and 50Mbps downloads; you can pick between either the 2.4GHz or 5GHz Wi-Fi bands; and you can connect up to 32 devices simultaneously – way, way more than most people will ever need.
Menu navigation is simple, and the clean UI makes the most of the two buttons and small screen to give you the info you need. For more complex setup – including USSD support, useful for connecting to many foreign networks – you can use either the web portal or free smartphone app.
The 3000mAh battery should give you an impressive 15 hours of working battery time. You even get a microSD slot, which supports cards up to 32GB and can be used as a quick way to share files between devices.
Many of the options in this chart are suitable for those who will regularly need the use of a mobile Wi-Fi router, but MyWebspot is more appropriate for those who have a one-off requirement.
If you’re going on holiday abroad (potentially outside the realms of free roaming in Europe) and have several devices to get online, the service allows you to hire a hotspot for use by up to five devices in more than 100 countries.
Daily charges are calculated based on where you are going and for how long. At first glance they might seem steep, but they are nothing compared to what your mobile operator will charge you once you overstep your data allowance. It can also be very expensive to connect to Wi-Fi provided by some holiday resorts, which is often slow and time-limited.
The data is technically unlimited, but once you exceed the fair usage (1GB/day in Europe, US and Canada; 2GB in Mexico; fully unlimited in South East Asia; and 512MB everywhere else) the speed drops to an almost unusable 256kbps.
Setup couldn’t be simpler. The device can be delivered directly to your resort (or home if you prefer), then you turn it on, wait a moment for it to connect to a local 4G LTE network, and pick it up on your mobile device as you would any other Wi-Fi network using the SSID and password printed on the label on the back. On your way home you pop it in the post box using the prepaid envelope.
MyWebspot claims download speeds up to 100Mbps, and uploads of up to 40Mbps. In our testing in Lake Garda, Italy, we recorded an average download speed of 33.5Mbps, and upload speed of 26.8Mbps. Naturally these speeds will decrease as you add multiple devices.
You’ll get about eight hours battery life from the Mi-Fi router, which is supplied with the appropriate local charger for your holiday destination.
There’s no companion app, which means even technophobes will get along with MyWebspot, though it would be handy to have some way of monitoring usage across multiple devices given that there’s no LCD screen.
If you’d rather buy a mobile Wi-Fi router on a contract, Three has some of the best deals right now. It uses the Huawei E5783B-320, and pairs it with some great data bundles.
We like the fact you can subscribe to a one-month rolling contract, because the way the world is right now no-one really knows how much they’ll be traveling over the next couple of years!
Three offers great value on unlimited data, with the one-month plan costing £27 per month (plus £39 upfront), the 12-month plan costing £26 per month (no upfront cost), and the 24-month plan costing £22 per month (again, no upfront cost). Purchase either the 12- or 24-month option and right now you get the first six months half-price.
If you don’t need this much data, 10GB and 40GB plans are also available, with the 10GB 24-month plan starting from £12 per month.
You can connect multiple devices: Some MiFi devices let you connect 10 or more devices to a single hotspot, which will work out a lot cheaper than paying for a mobile data plan for each of those devices – but you’ll want a generous data allowance.
You can connect Wi-Fi-only devices to a mobile data connection: Tablets are great to use at home, but what about on the train, on the beach or by the pool? Wherever you can get a phone signal, you can use MiFi to create a wireless network and get online from any Wi-Fi device.
You can save money on your next tablet: Buying a tablet with a 4G or 5G data connection adds around £100 to the price, and that’s before you consider the monthly fee for your data. Use some of that money to buy a MiFi router instead and you’ll never need to buy a cellular tablet again.
You can reduce roaming charges: Most mobile operators offer free roaming in the EU (for now, anyway!), but fixed-fee roaming elsewhere, allowing you to take your home tariff with you for a set cost. Rather than paying this extra charge on all your devices, turn off data roaming on them and connect them all to a mobile hotspot. You’ll pay this charge only once, but get all your devices online. Note that 5G roaming is not widespread, but it is currently offered by Vodafone and VOXI.
You can avoid using slow hotel Wi-Fi: When visiting hotels that still charge for Wi-Fi, you can get the kids online all day and at a lower cost than what the hotel would charge. Better still, you can avoid using the same network as all the other guests, which is usually slow and often has poor signal in your hotel room. Sometimes these networks can also be unsecured, so using MiFi will be preferable.
You can add 5G connectivity to a 4G device: Many of us have yet to jump on the 5G bandwagon, but where available it is seriously fast. Although your phone may be limited to 4G, your data plan almost certainly includes 5G. A 5G mobile router will allow you to connect your 4G phone to the internet at 5G speeds.
You can get faster download speeds: Even if your device already supports 5G, you could potentially get faster download and upload speeds by switching to a MiFi that supports a faster connection. Just remember that 5G is not yet available everywhere, and purchasing a 5G hotspot will push up the price.
You can share storage across your own mobile network: If your MiFi supports a microSD card, you can share that storage across all your devices, which is especially handy if they don’t support expandable storage themselves.
There are three options when purchasing a mobile Wi-Fi router:
Many people will automatically go to their mobile operator for a MiFi device, since it’s an easy solution and you don’t need to pay anything up front. But this isn’t always the best idea.
If you buy a MiFi router from a mobile operator it will probably be locked to that network, preventing you from shopping around for the best data deal. You will also most likely pay over the odds if you choose to pay nothing up front but tie yourself into a two-year contract.
However, buy a network-unlocked router and shop around for a great-value data SIM plan and you will save money in the long run.
Note that the mobile hotspots offered by UK mobile operators are typically made by Huawei, but also Netgear, HTC and TP-Link. If you know the model you can usually find these devices available network-unlocked through retailers such as Amazon.
Technically, yes. If you have a significant or unlimited data allowance with your mobile tariff you could simply take the SIM out your smartphone and insert it into a mobile router.
However, not all mobile operators support unlimited tethering (check your contract), various phone functions are not going to be available on your smartphone while it’s missing its SIM, and you might regret the decision if you are overly generous with that shared mobile Wi-Fi connection and run out of data some time before the allowance renews.
You can now purchase data SIMs or SIM-only plans with big data allowances on PAYG or contract from all the UK’s major mobile operators. Which option you choose is largely going to be based on how much data you need to use, and how frequently you need to use it.
If you want something only for when you go on holiday, choose a PAYG plan and pay for data only when you need it. If you want something to get around a flaky home broadband connection or for use on your daily commute, choose either a rolling one-month contract option or save a bit of money with a 12- or 24-month plan.
We’d advise looking for a deal from a well-known mobile operator that has reliable coverage in your area (or your holiday destination), with a big data allowance, no restrictions on tethering, free or cheap roaming, and a low monthly or PAYG cost.
You can check network coverage in your area for 2G, 3G, 4G and 5G on the mobile operator’s website. Use the following links to jump straight to the major UK mobile operators’ coverage checker: Vodafone, EE, O2, Three, GiffGaff, Smarty, VOXI, iD Mobile, Virgin Mobile, TalkMobile.
There are many more companies offering data SIMs than we have listed here, but all are what are known as MVNOs, or mobile virtual network operators. This means they piggyback on another mobile network (Vodafone, EE, O2 or Three) for connectivity. As long as you have coverage with the big four, all the MVNOs should be covered in your area.
The best data SIM deals are always changing. We’ve collated more in-depth advice in our frequently updated guide to the best SIM-only deals, but our preference currently falls to Three. All its SIMs support 5G.
Smarty, which also runs on Three’s network, currently has a great deal on 40GB of data for £10 on a12-month plan. Tethering is unlimited in the UK.
4g wifi modem Marie is Editorial Director at Foundry. A Journalism graduate from the London College of Printing, she's worked in tech media for more than 17 years, managing our EMEA and LatAm editorial teams and leading on content strategy through Foundry's transition from print, to digital, to online - and beyond.