Pile of old phones

SIM cards for old phones

With technology advancing at such a rapid pace, it can be difficult keeping up to date with the latest products. And rather than bearing the expense of a new phone, many people prefer sticking with their tried and tested mobiles, simply updating the SIM if and when needed.

But given the different SIM cards now available in today’s market, how exactly do you determine which is right?
In this guide, we look at different SIM cards for old phones and explain which of these are sure to breathe new life into your trusty handset!

Can you use new SIM cards for old phones?

Yes, you can buy a new SIM card for your old phone - but you must make sure it fits first.

As technology has changed over the years, SIM cards too have been redesigned and updated, which means checking which SIM is compatible with your old phone is absolutely essential.

If you choose the wrong SIM card for your old phone, it won’t work and a replacement chip will be needed to make the device usable.


What size SIM do you need?

Depending on the age of your phone, the SIM can be one of three sizes: Standard, Micro and Nano.

The good news is that SIM card technology has remained more or less the same since it was first introduced, so you only need to make sure the sizing is correct for a fully compatible chip.


What size do SIM cards normally come in?

If you’re asking yourself ‘what SIM card do I need’, you must bear in mind that SIM size usually comes down to the amount of plastic surrounding the chip.

Old phones usually have more space inside, due to the absence of certain technologies. This means that they often support Standard SIMs, which come with thicker plastic edges.

As space becomes more and more of a premium in smartphones, trimming borders around the cards has led to Nano SIMs. These are essentially as small as a SIM can get and have become the go-to SIM size in modern devices.

The typical dimensions of different SIM cards are:

Graphic showing SIM card dimensions

A straightforward internet search or quick check with a ruler will help determine your own SIM’s measurements.

It is worth noting that Standard SIM cards can also be referred to as ‘Mini’ SIMs, so try not to confuse them with other varieties when you purchase your new chip.


SIM cards with Asda

When you order a SIM card with us (be it a pay as you go SIM or a great value bundle), we’ll send you a card that can work in any device. When you receive the SIM, it’ll resemble a standard SIM card, but you can actually pop the inner chip out to whichever size you need.

This also means if you ever change phones, you can simply carry on using the same Asda SIM!


How do you activate your new SIM card?

Any mobile phone that uses SIM technology has a tray where the card gets inserted. To locate this, simply take off the back cover.

Then it’s just a case of removing the old SIM and adding your new one.

Activate a new SIM with comprehensive help from Asda mobile, including our walkthrough video plus six easy steps to follow so that you can get your old phone working again.


How to check if a new SIM is working in your old phone

First, confirm whether your mobile network is displayed. (By mobile network, we mean 4G, LTE, 5G, etc.) This should be visible in the top right corner of your screen.

If you can’t see the network there, chances are the SIM isn’t working properly and will need to be reinserted.

Also, you should be able to make and receive calls. The SIM card is what allows mobile phones to do this in the first place, so try calling a friend or loved one - and have them call you back for added assurance.

Finally, ask someone you trust to send a test text message. Your SIM will only deliver their message once it is working correctly. If nothing comes through, you’ll know there’s a problem that needs to be fixed.


Check out amazing SIM only bundles from Asda mobile and give your old phone a new lease of life!

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