If you want more than one phone number on the same device, or multiple networks on that single handset, you'll need a dual SIM phone. You likely found your new SIM on our best SIM only deals guide, right? More than one that appeals? Time to get dual SIM enabled.
But why have dual SIM and how does this multi-SIM magic actually work?
Why do I need dual SIM?
There are many reasons you might want more than one SIM in a phone but a common one is having two numbers. You might want to have your personal phone number and your work number on the same device. This saves you carrying around multiple handsets, potentially having multiple chargers to think about and maintaining more than one device.
Or perhaps you go to various places where one network doesn't offer enough coverage. By having more than one network option in your phone that means you're more likely to get connected no matter how far afield you venture.
Whatever your reason for having a dual SIM setup, you'll need a smartphone that can handle the task.
How does a dual SIM smartphone work?
The most basic part of a dual SIM phone, that other handsets don't have, is a tray that can load in more than one SIM, obvious, perhaps. But with eSIM becoming more common you may find dual phone numbers on one device without loading in two SIMs.
But for now, most dual SIM setups use a dual SIM smartphone. These break down into two types: DSDA and DSFA.
The first, Dual SIM Dual Standby, will put one SIM on standby as the other one is in use. Yup, that means the other line will be engaged if anyone tries to call. Not ideal for business users then.
Dual SIM Full Active is the other option. This allows you to have both SIMs constantly connected, so you can receive two calls at once. Allowing you to jump between calls if needed.
Can I use multiple networks on a dual SIM phone?
You can technically use two different SIM networks on the same phone. But, like with a single SIM, some phones are locked to the network provider.
So you'll need to take this into consideration when buying the phone. If you buy the phone offline, or SIM only, then it likely will not be locked, allowing you to use any two networks you decide on.
What are the best dual SIM phones?
There are lots of dual SIM options out there right now but they're all Android. So if you're team Apple and want to go dual SIM you'll need to jump ship. That or carry two handsets with you.
Some top dual SIM smartphones include the OnePlus 8 Pro, Huawei P40 Pro, Honor View 20, Oppo Find X2 Pro and Samsung Galaxy S20.
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