Dual-SIM smartphones let you use two SIM cards 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.
Dual-SIM phones are also useful for maintaining two personal contracts, 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 local SIM for when you're at home and another that is local to the country you're visiting.
These days, you don't always need two physical SIMs to achieve this dual-SIM functionality. For example, Google's Pixel 6 supports dual-SIM via eSIM, which means you can have one standard SIM installed in the phone and subscribe to another network via its eSIM. For more on this, see What is an eSIM?
Dual-SIM phones are incredibly popular outside the UK, but for some reason, us Brits have been left out of the dual-SIM party. This is one reason why the Chinese market has become a popular solution for picking up a dual-SIM phone.
Do bear in mind that many smartphones officially sold in the UK are single-SIM variants, whereas alternative models of that very same phone sold elsewhere in the world are dual-SIM. If you have a specific phone in mind, a good place to check is Amazon for any dual-SIM variants of that phone.
Xiaomi Mi 11 - Best Overall
- Fast performance
- Great camera
- Attractive design
- Phenomenal value
- MIUI still sorta sucks
- No IP rating
- No telephoto
The Mi 11 is a fantastic bit of hardware for the price. The fastest chipset around, a beautiful display, and strong cameras are all packaged within a lovely bit of industrial design.
Some will miss the IP rating, though for me the bigger downsides are the choice of a macro over a telephoto lens, the only average battery life, and a software experience that still lags behind the key rivals.
Before you buy this phone, do note that the Xiaomi 12 is imminent, having already been unveiled in China.
Read our full Xiaomi Mi 11 review
Samsung Galaxy S21 Ultra - Best Camera
- Excellent camera and performance
- Great battery life
- Beautiful display
- No charger may irk some
- Loss of microSD slot
- It's big
After 2020's disappointing Galaxy S20 Ultra, Samsung has finally earned the name with a follow-up that delivers almost everything you could want from an Android flagship - admittedly at a price that only a few can afford, and in a form factor that will simply be too big for some.
The camera is now probably the best in any phone, with a 108Mp main shooter backed up by an ultrawide and two telephoto lenses at different zoom levels.
The expansive 6.8in display delivers both high WQHD+ resolution and adaptive refresh rate up to 120Hz, and with new S-pen stylus support it comfortably fills the productivity niche of the Galaxy Note 20 Ultra too.
As with the Mi 11 above, do note that the successor to this phone will likely be unveiled in early 2022.
Read our full Samsung Galaxy S21 Ultra review
Oppo Find X3 Pro - Best Display
- Best-in-class display
- Excellent battery life
- Phenomenal cameras
- No periscope lens
- Some performance throttling
The Oppo Find X3 Pro is a phenomenal phone by any measure. The 6.7in 10-bit 120Hz QHD+ panel is one of the best displays in any phone right now and Oppo backs it up with 65W wired and 30W wireless charging, a 4500mAh battery, and a top-tier camera that boasts 50Mp sensors on both the main and ultrawide lenses.
You’ll have to live without a periscopic zoom lens - the telephoto here is a measly 2x zoom - but Oppo instead includes a novel microlens camera capable of microscopic super-closeups. That's not the only oddity, as the design itself is utterly unique thanks to a seamlessly sloped camera module built right into the glass of the phone's body.
For pure performance the Find X3 Pro is also hard to beat, with all of the above plus a Snapdragon 888 chip, 512GB storage and 12GB RAM. You just have to be willing to pay the price, as it doesn't come cheap.
Read our full Oppo Find X3 Pro review
Samsung Galaxy S21 - Best For Ease Of Use
- Improved battery life
- Superb performance
- Decent software
- Nice design
- Cameras are relatively unchanged
- Some downgrades from S20
- No charger
On the surface, Samsung has brought better specs - including 5G as standard and the latest Snapdragon 888/Exynos 2100 chip - to the table for less than the asking price of the 4G-only build of the Galaxy S20.
In actuality, it's prioritised those upgrades to ensure the S21 appears as relevant and current as possible, without going out of its way to really set the bar for forthcoming 2021 rivals.
The Galaxy S line's unofficial position as the 'default alternative' to those who don't want an iPhone isn't likely to change with everything the Galaxy S21 has to offer, and for most users, this is still as much of a well-rounded, capable and reliable device as the S20, S10 and beyond have been.
If you're looking for Samsung to push the flagship phone envelope, however, the Galaxy S21 isn't the phone to do it.
Read our full Samsung Galaxy S21 review
OnePlus Nord 2 - Best Mid-range Phone
- Excellent software
- Great design
- Strong all-rounder
- Only 90Hz display
- Slightly thick
An outstanding follow-up to 2020's best mid-range phone, with great performance, 5G, OnePlus's signature Oxygen OS user experience, and a near-flagship main camera. What's not to love?
What the OnePlus Nord 2 really demonstrates is the company's ability to prioritise the features that users are looking for right now and wrapping them up in an attractive package with a compelling price point.
The Nord 2 misses out on flagship niceties like wireless charging and waterproofing, but those are really the only compromises made here.
Read our full OnePlus Nord 2 review
ZTE Axon 30 Ultra - Best Value Flagship
- Incredible camera
- Stunning screen
- Svelte design
- Great value
- No wireless charging
- No microSD slot
The ZTE Axon 30 Ultra is a stunning proposition and offers buckets of value. It’s a genuinely exciting flagship smartphone in practically every department: it’s lightweight, feels great in the hand, the 144Hz 6.67in AMOLED display is detailed and crisp, the Snapdragon 888 allows it to perform like a gaming phone and, well, that camera setup is incredible.
Comprised of three 64Mp snappers and a 5x telescope lens, the Axon 30 Ultra’s rear camera offering is versatile, and unlike some, images captured across all sensors are comparable in terms of quality, detail and colour balance.
There are plenty of creative shooting modes available to make the most of the system, and it caters to videographers with [email protected] video recording too.
The results are comparable to those taken on ultra-premium smartphones like the Galaxy S21 Ultra and iPhone 12 Pro, but with one key difference – it’s hundreds of pounds/dollars cheaper.
The software could do with a visual tweak here and there and there's no wireless charging, but those are minor complaints in what is an otherwise phenomenal 2021 flagship.
Read our full ZTE Axon 30 Ultra review
Xiaomi Poco X3 Pro - Best Performance on a Budget
- Phenomenal performance
- Big 120Hz display
- Long-lasting battery
- Big and bulky
- No 5G
- Average camera
The Poco X3 Pro is a phone designed for Android gamers or power users on a budget, though it might also appeal to those who want to go big on specs in order to futureproof their phone.
If pure performance isn’t your priority, then you can find phones that are slimmer and lighter, with better camera performance, for around the same price.
What you won’t find is any phone that can match this pound for pound right now. This is near-flagship processing power in one of the cheapest phones on the market, and it’s almost ludicrous that Xiaomi has pulled it off.
Read our full Xiaomi Poco X3 Pro review
Xiaomi Redmi Note 10 Pro - Recommended
- Stunning 120Hz AMOLED display
- Long battery life
- Excellent cameras
- No 5G
- No OIS
- Huge camera bump
- MIUI not for everyone
The Redmi Note 10 Pro is essentially an upgraded Poco X3 NFC with a nicer display and better camera.
The 6.67in 120Hz panel boasts AMOLED tech, meaning superb contrast and vibrant colours. The 108Mp lead camera, meanwhile, excels and comes accompanied by a pair of secondary snappers that exceed expectation.
Fun extras like 33W fast charging, a headphone jack and even an IR blaster elevate the Redmi Note 10 Pro from good to great budget offering, considering what Xiaomi's incorporated here.
Read our full Xiaomi Redmi Note 10 Pro review
Asus ZenFone 8 - Best compact phone
- Compact build
- Snapdragon 888
- IP68 waterproofing
- Plain design
- Weak battery life
Like the Realme GT, the Asus ZenFone 8 is in many ways a proper flagship phone - it's simply one that's been priced aggressively enough to make the cut in our mid-range chart.
You get flagship features like a Snapdragon 888 chipset, fast RAM, and even an IP68 water-resistance rating - though there's still no wireless charging, sadly.
It's also lightweight and compact, with a 5.9in display and weighing just 169g, making it one of the smallest Android phones around - though sadly this does come with an inevitable compromise on battery life.
We much prefer the ZenFone 8 to the more expensive ZenFone 8 Flip, though that phone does boast a neat flipping camera module.
Read our full Asus ZenFone 8 review
Xiaomi Poco F3 - Recommended
- Superb performance
- Excellent OLED display
- Impressive cameras
- Underwhelming battery life
- MIUI not for everyone
The Poco F3 is a cracking mid-range phone. Stellar hardware is led by Qualcomm’s 5G-enabled Snapdragon 870 chipset, which delivers excellent performance across the board.
That extends to gaming, where the 120Hz OLED display comes into its own. However, that high refresh rate does hit battery life, especially when you’re working with a smaller capacity than the Poco X3 Pro. The software is also still an acquired taste, despite big steps forward for MIUI in recent years.
A premium design and solid set of cameras make for an excellent smartphone experience, but the strength of the competition makes it more difficult to recommend.
Read our full Xiaomi Poco F3 review
Your buying guide to the best dual-SIM phones in 2022
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/5G, or even what size SIM cards they accept.
You can never assume; you'll need to contact the manufacturer or check spec tables, reviews or forums to find out this information.
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-active SIM phones use two modems and allow you to receive calls on both numbers at once.
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 as 'Always Ask'.
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 4G or 5G connections, you can use data connectivity on only one SIM at a time.
Unlike with calls and texts, typically speaking 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 - though some phones will let you set them to switch to the other SIM when the first can't make a connection.
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.