Your buying guide for the best dual-SIM phones in 2017

Dual-SIM smartphones let you use two SIMs in a single phone. Most people who use dual-SIM phones find the functionality useful for mixing work and pleasure, rather than carrying separate phones for their work- and personal contracts. See all phone reviews

Also see: Best Phone Deals

Dual-SIM phones are also useful for maintaining two personal contracts, however, whereby one might offer a good rate on calls and texts, and the other offers unlimited data. Or perhaps you frequently travel abroad, and would like to carry a UK SIM for when you're at home and another that is local to the country you're visiting. Also see: Best kids' phones 2017

Whatever your reason for requiring a dual-SIM phone, a problem in the UK is that most smartphones do not include the functionality as standard. Indeed, hardly any of the UK phones we are sent for review are dual-SIM models, and even where dual-SIM versions are available they are rarely intended to go on sale in the UK. Also see: Best smartphones 2017 

Dual-SIM phones are incredibly popular outside the UK, but for some reason us Brits are being left out of the dual-SIM party. And we want in. 

This is one reason why the Chinese market has become a popular solution for picking up a dual-SIM phone, but there are risks involved - read our advice on buying grey-market dual-SIM phones. 

Another way you can find a dual-SIM phone is to search a site such as Amazon or eBay for 'dual-SIM phone', 'dual-SIM Samsung' or 'dual-SIM Sony' and so on. Having seen the standard single-SIM versions that are intended for UK sale we have no doubt that many of these are great phones, but having not personally laid our hands on the dual-SIM variants we're reluctant to recommend them here.

They also tend to go off sale as soon as we add them to the round-up. Of course, you are more than welcome to recommend these phones in the comments below.  

In this group test we recommend only phones that are sold in the UK with dual-SIM functionality as standard, and that we have personally reviewed. And in the future, we're hoping that the increased demand for dual-SIM phones means we will begin to see more and more dual-SIM smartphones supplied to us for review. Also see: Best budget phones and best phones under £50. 

How do dual-SIM phones work? 

Something we've noticed when shopping for dual-SIM phones is that the manufacturer very rarely provides any information about the functionality other than it exists. It doesn't tell you how the dual-SIM functionality works in practice, nor whether both SIMs support 4G, or even what size SIM cards they accept.

As we've learned you can never assume: you'll need to contact the manufacturer or check spec tables, reviews or forums to find out this information. 

For that latter concern, as technology journalists who are always having to swap SIMs between the various phones we have in for review, we have found the best solution is to adopt a Nano-SIM for our personal smartphone, then pair it with an adaptor when we need to use it in a phone that supports Mini- or Micro-SIMs. SIM adaptors are very cheap, but some are better than others.

We like the MediaDevil Simdevil, which comes with Nano- to Micro, Nano- to Mini and Micro- to Mini adaptors, plus a SIM tray ejector tool. It costs £1.97 from Amazon. If you're planning to stick with the phone, however, you can always request a new SIM of the correct size for free from your network operator, then swap over your number. Also see: Best sounding phone 2017.

In all the dual-SIM phones we've tested both SIMs are on standby at all times (known as dual-standby phones), but you can actively use only one SIM at a time. This means that either SIM can accept a phone call or text at any time, without you having to actively swap between them or reboot the phone.

However, if you get a call on one number while a call is active on the other, it won't start ringing in your ear or give you the option to put the first caller on hold - the call will simply not be successful.

What is the difference between Dual-Standby and Dual-Active?

Dual-standby phones require you to specify one SIM or the other for data, though unless specified you can choose between the two on the fly for calls and texts.

Dual-active SIM phones also exist, which use two modems and allow you to receive calls on both numbers at once. We've not tested any dual-active phones. See also: Best Android smartphones in UK: What's the best Android phone you can buy in 2017? 

If it's you who wants to make a call or send a text, Android has a standard SIM Management menu that lets you specify which SIM should be used for voice calls, video calls, messages and mobile data. You can either specify a particular SIM for each of these tasks, or leave the setting at Always ask.

If you choose the latter, the next time you want to make a call or send a text you will be asked which SIM you want to use. 

8 best dual-SIM smartphones of 2015: The best phones into which you can put two SIM cards - best dual-SIM phone reviews - dual-sim phone buying advice

The data connection is where there seems to be a lot of confusion when it comes to dual-SIM phones. Whereas both SIM slots on some dual-SIM phones are capable of supporting 3G or 4G connections, you can use 4G on only one SIM at a time.

Unlike with calls and texts the data connection can't be on standby for both SIMs: you must specify which SIM you want to use rather than select one when prompted. 

Of course, this isn't always the case, and some phones support 3G/4G only on their first SIM slot, and you can't change the data connection for browsing the web or making video calls. You can still specify which SIM should be used for calls and texts. 

8 best dual-SIM smartphones of 2015: The best phones into which you can put two SIM cards - best dual-SIM phone reviews - dual-sim phone buying advice

By default, when you are using the data connection on one SIM and a phone call comes in to the other it will pause the data connection on the first.

In the Moto G you'll find a Connection priority menu, which lets you specify that calls should instead go to voicemail instead of interrupting your browsing. There is no such option on the other dual-SIM phones we've tested, but it's not something we'd be likely to change in any case. Also see: Best new phones coming in 2017. 

8 best dual-SIM smartphones of 2015: The best phones into which you can put two SIM cards - best dual-SIM phone reviews - dual-sim phone buying advice

Another issue when using dual-SIM phones is where your contacts are stored. We found that by default the contacts from both SIM cards are stored in the phonebook.

If you'd rather see the contacts from only one SIM, tap the three dots icon (within the Contacts app) and choose 'Contacts to display'. You can then select All contacts, Gmail contacts, phone contacts or one of your two SIMs. 

Usually when you add a contact you get a pop-up menu asking whether you want to store the contact on your phone memory, your SIM or your Google account. Here you'll now see two SIMs in the list rather than one.

A quick way to turn this off and prevent you always having to choose is to open the SIM management menu, select Contact binding and then select a specific SIM.

How to get a second phone number

Physically inserting a second SIM into a single-SIM phone would be impossible without altering its design in some way, but it is possible to achieve the same feat by adding a second phone number.

OnOff is an app for iPhone and Android that lets you have multiple phone numbers on one phone. Right now it supports French and UK numbers, which work like any other number for receiving phone calls and text messages. More conveniently, though, you can turn off these numbers when it suits.

This means you could potentially give your work colleagues or clients one phone number that is switched off outside office hours. Or you could give your friends a number that is switched off during office hours.

Another bonus: should your phone battery die, you can log into the app on a friend's phone and still get your calls and texts.

The app itself is free, and you get a free trial with limited functionality for one phone number. If you like it you can then 'activate' that number, which unlocks all the features of the app. You can set up multiple lines, though these must be paid for too.

OnOff pricing starts at £2.99 per month, with full details here.

Best dual-SIM phones 2017 UK - best dual-SIM phone reviews

1. OnePlus 3T

OnePlus 3T
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 28 March 17
  • RRP: From £399, From US$439

The OnePlus 3T will be unfairly compared, for now at least, to the phone that came before it. So let’s ignore it. On its own, the OnePlus 3T is everything a modern smartphone should be; slim, fast, and responsive, with above average battery life and cameras that produce stunning images. And then there’s the price. OnePlus may not like being known for it, but £399 remains an absolutely amazing price point for the phone on offer.

As long as you don’t want an iPhone, this Android handset stands side by side with the Samsung Galaxy S7 as the best example of a smartphone on the market today – once we’ve all got over that it came a little sooner than we had expected.

Read our OnePlus 3T review.

2. Xiaomi Mi5s

Xiaomi Mi5s
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 29 November 16
  • RRP: £282.75, US$352.69

We cannot recommend the Xiaomi Mi5s enough. This is the smartphone every 2016 flagship wanted to be, and it comes with a price tag half that of theirs. Fantastic build quality, fantastic performance, fantastic storage, battery and connectivity options - the Xiaomi Mi5s gets a big thumbs-up from us.

Read our Xiaomi Mi5s review.

3. Xiaomi Mi Note 2

Xiaomi Mi Note 2
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 13 March 17
  • RRP: £497.04, US$619.99

The Mi Note 2 was wrongly overshadowed at its launch. This is a gorgeous big-screen Android phone with very decent performance, a great camera and plenty of storage. We'd like to see a Quad-HD screen on Xiaomi's flagship phone, but this one should prove plenty sharp and clear. Google apps are not preinstalled, but there is a workaround if you are happy to do some tweaking.

Read our Xiaomi Mi Note 2 review.

4. Xiaomi Mi Mix

Xiaomi Mi Mix
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 23 February 17
  • RRP: £799.91, US$997.78

It might sound expensive, but the £799 Xiaomi Mi Mix actually offers very good value when you consider its meaty core hardware and generous 256GB of storage - it's certainly less than you'd pay for an iPhone 7 Plus. This isn't a phone you buy with budget in mind, however: the Mi Mix is the phone you buy when you want onlookers to say "Oh my gosh, what is that? It's amazing - I want one of those!" The Mi Mix is a revolutionary phone that we hope is a sign of things to come, with that gorgeous bezel-less display, beautiful ceramic body, fantastic performance, long, long battery life and all the other fancy tech we can't even pronounce, let alone understand. No matter - it works. Highly recommended.

Read our Xiaomi Mi Mix review.

5. Meizu Pro 6 Plus

Meizu Pro 6 Plus
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 5 May 17
  • RRP: £399.05, US$512.99

Running Flyme OS 5 out of the box, the well-built Meizu Pro 6 Plus is a fantastic Android phone with some seriously good performance, a vibrant and high-resolution screen and a decent camera. Unfortunately, though cheaper than UK flagships, at £399 (before import duty) it’s still too pricey to properly compete with the Galaxy S7 and OnePlus 3T. Neither are we in love with Flyme OS.

Read our Meizu Pro 6 Plus review.

6. Moto G5

Moto G5
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 21 April 17
  • RRP: £169

There’s plenty of competition in Android’s budget market, but the Moto G5 is the best around right now. The build quality alone feels like it belongs on a much more expensive phone, while the fingerprint gesture controls genuinely improve the Android experience. The benchmarks and battery hold it back, but they're not unreasonable given the price - and you won't find a much better looking phone at £169.

Read our Moto G5 review.

7. UMIDIGI Z Pro

UMIDIGI Z Pro
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 21 April 17
  • RRP: £204.35, US$247.99

The UMIDIGI Z Pro offers fantastic value at just over £200. It has a large battery, a decent screen and powerful performance. The dual-camera doesn't offer quite the relief we were hoping for following poor performance from the UMI Z, but this is still a great phone.

Read our UMIDIGI Z Pro review.

8. UMI Z

UMI Z
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 31 January 17
  • RRP: £239.99, US$239.99

The UMI Z is an excellent-value Android phone with a large battery, a decent screen, the most powerful MediaTek processor you can get and a very good selfie camera. Unfortunately the primary camera doesn't quite live up, but it's otherwise difficult to fault. With full UK 4G connectivity it's a great buy.

Read our UMI Z review.

9. Honor 8

Honor 8
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 5 September 16
  • RRP: £369.99, US$399

The Honor 8 is a fantastic smartphone, but the price has gone up from the Honor 7. In return for the additional expense you get a fantastic dual-camera, a sleek and stylish design, a faster fingerprint sensor and a beautiful display, which combined make the Honor 8 a worthy competitor to the OnePlus 3.

Read our Honor 8 review.

10. Lenovo P2

Lenovo P2
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 26 January 17
  • RRP: £199.99

The Lenovo P2 is really being sold on the strength of its battery, and the great news is that it lives up to the company’s hype, offering you days of usage and a power bank in a pinch. Throw in the premium design and build quality, and you have a phone that delivers tremendous value for money. It may not boast flagship performance, but by the time you hit your third day without charging, you’re not likely to care that much.

Read our Lenovo P2 review.

11. Samsung Galaxy A7 2016

Samsung Galaxy A7 2016
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 5 July 16
  • RRP: £399

The new Samsung Galaxy A7 for 2016 is a great-looking upgrade over its predecessor, with outstanding battery life and a few other welcome tweaks, but there is no escaping the fact it is overpriced at £399. That’s even more apparent when you consider the better-specced, more fully featured and significantly faster Galaxy S6 is available for £40 less.

Read our Samsung Galaxy A7 2016 review.

12. Elephone S7

Elephone S7
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 12 January 17
  • RRP: £177.11, US$219.99

The Elephone S7 is a very good-looking phone at an affordable price, with decent performance and a generous helping of storage. On the down side the cameras are disappointing and the rear panel is plastic. Even at this price you don't need to compromise so heavily.

Read our Elephone S7 review.

13. Xiaomi Redmi Note 4X

Xiaomi Redmi Note 4X
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 8 May 17
  • RRP: £164.76, US$202

It isn’t a huge upgrade over the Redmi Note 3 or Note 4, but the Note 4X Global edition is a fine budget phone for UK users.

Read our Xiaomi Redmi Note 4X review.

14. Ulefone Future

Ulefone Future
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 14 July 16
  • RRP: £188.57, US$244.46

Ulefone has attempted to build a futuristic phone with the Future’s edge-to-edge display and USB-C port. For a mid-range Android phone performance is good, and the design is good, even if the phone is on the heavy side. We can’t turn a blind eye to the camera quality, although a software update should be able to fix the issues we saw.

Read our Ulefone Future review.

15. Xiaomi Mi Max

Xiaomi Mi Max
  • Rating: ratingsratingsratingsratingsratings
  • Reviewed on: 29 June 16
  • RRP: £212.04, US$274.89

If you want a huge phone and you don’t want to pay as large a wedge of cash, the Xiaomi Mi Max is a fantastic phablet with good looks, decent performance, strong runtime and, most importantly of all, a gigantic screen. Not ideal for novice users, but otherwise the Mi Max is a highly recommended smartphone.

Read our Xiaomi Mi Max review.