If a phone is due to run out of software updates - including important security updates - in less than a year, we can't recommend you buy it.
Security updates help to protect your phone against new and emerging threats, and without them, it's at greater risk of hackers and malware.
Read on to find out what this means for you and how to check whether your phone is still being supported.
Find out more about mobile phones and the importance of security updates.
When you buy a new phone, you'd expect to be able to hold onto it for at least a year before it needs replacing. But our research reveals that many phones on sale now will run out of software support in less than 12 months.
Of over 450 models in our phone support calculator (see below), we estimate 40% have less than a year of support left - and 24% are likely out of support altogether.
This means that if you enter into a typical two-year contract, your new phone could be using outdated and potentially insecure software before you've even finished paying it off.
We already remove a Best Buy when a phone drops off the update cycle, but now all phones with less than a year of support won't receive our endorsement.
The scores will stay the same, so you can still compare the hardware, but we can't recommend buying a phone that you'll need to replace so soon after purchase.
When your phone pings to let you know a new update is ready, it can be tempting to ignore it. But these updates not only contain patches that can improve your user experience - more importantly, they fix bugs that can be exploited by malware.
Phone manufacturers don't send out these updates forever, though, and some only provide them for two years after the phone's launch. Without this vital security support, your phone could become insecure and, in an worst case scenario, your data could end up in a hacker's hands.
In an ideal world, your phone would tell you how much longer it will be supported for, and when it receives its last security patch, so you know exactly when it's time to upgrade.
Brands aren't always transparent though, and even when they are, it can be tricky to find the information you need. However, our phones support calculator tool can help - enter a model below to see how much longer a phone will be updated.
If you're nearing the end of your support period, you should start thinking about buying a new handset. You're unlikely to be at any immediate risk, but the chances of a being hacked increase the longer you leave it. Read our guide on for more.
If you're looking to buy a phone that you can keep past a typical two-year contract, the brand you opt for is an important consideration.
Unfortunately, it's usually the cheaper brands with the shorter update cycles, so you need to weigh up the benefits of a cheaper phone that you may need to replace sooner, with the premium price of a phone that will last longer. However, a longer support period means you can choose an older discounted handset, which might bring the price down.
Typically, phone manufacturers offer a minimum support period of two to five years for their handsets.
It's all very well equipping phones with longer-lasting hardware such as waterproofing and stronger glass screens, but if the software can't keep up, you'll need to replace it before its time is up.
These short update cycles leave consumers exposed to potential threats, force them to spend more on new handsets and contribute to the huge e-waste problem. We believe that brands can and should do more, including: