Why your SIM card is not detected on your Android or iPhone

Using a SIM card is probably the easiest way for you to get internet access to your phone or tablet. You can also use it to make calls and texts, though many of us nowadays are more reliant on the web access, so you can message via Whatsapp and video call via Skype or Zoom.

SIM cards are generally pretty reliable (unlike your mobile data not working), and aside from getting gradually smaller, they typically work in a similar fashion to a decade ago. Unfortunately, though it’s a less common problem now, you may still get a notification that your SIM CARD cannot be detected.

Here’s what you should do if you get that message on your Apple or Android smartphone or tablet.

Why your SIM card is not detected on your Android or iPhone

It may go without saying for some, but you’ll need to have an active plan on the SIM card for your phone to read it. If it’s a PAYG SIM that you haven’t yet registered, then it won’t actually be detected properly until you activate it.

Turn your phone on and off

As with most things related to tech, turning your device on and off again is usually the best thing to start with.

If there’s been an error in start up, then restarting your phone can often quickly fix the issue. When you restart a phone, you’re refreshing its memory and wiping the slate clean. And when you clear the memory, everything your phone has previously been doing is erased.

When you turn it back on again, it’ll start all over agin. It’s kind of like having the opportunity to restart your morning if you’re having a bad day at work. And, more often than not, it actually works to fix the problem.

Make sure your OS is updated

It doesn’t matter what type of operating system you’re using, it’s best to update it on a regular basis. Both Android and iOS users should always make sure that their OS is updated.

If you don’t keep it updated, then this can cause issues with the software on your phone reading its SIM card. This can happen when your operating system is outdated, as usually the OS is updated to fix any potential bugs.

The good news is that it’s really easy for you to do this within your phone settings. It’s one of the first things that you’ll want to do to ensure the software on your phone isn’t preventing it from working with your SIM.

Clean your SIM card

It could be that your device can just not read your SIM card properly due to the way it’s positioned. Or, there could be some debris or dust on the SIM itself that’s stopping it from being read.

Taking the SIM out and giving it a wipe over with a cloth should only take you a few seconds, but it’s definitely worth doing. If you’ve got an iPhone, you’ll also want to make sure that the card is placed into the tray properly to ensure that it fits into the reader.

Try using another SIM card

If you can find another phone with the same sized SIM card, then it’s definitely worth trying another SIM card in your phone.

It could be that you’ve actually got a problem with the phone reading the SIM, as opposed to just the SIM card itself. We can quickly find out if this is the case by trying a different SIM card in the phone and seeing if that works instead.

It’s a good sign if you try another SIM card in the phone and it works. This basically means that there’s a problem with the SIM card itself. They’re easily replaced, and you can usually order a new one from your data provider within a few days.

Switch it on (Dual SIM only)

Some models of newer Android phone have the ability to use two different SIM cards. This comes in handy if you’re often travelling in and out of the country, as you can easily switch between them.

However, in some cases it may mean that your primary SIM isn’t enabled within your phone’s settings. This can be the case if you’ve just bought a new phone, as it may have the other SIM slot as a priority.

You should be able to go into your settings very easily and turn on the correct SIM card. It’s a simple one and fairly unlikely, but it’s worth checking all the same.


So altogether, there are a few different reasons why your SIM may not be working. Making sure everything on your phone is fully updated is always one of the first things you should do.

If none of the above have helped you out, then it may be worth getting in touch with your phone company. They can let you know if the SIM is activated, and if necessary, they’ll usually send you a new one free of charge.

Avatar of Jon
About Jon

Hey, I'm Jon. I'm an engineer by trade, so it makes sense that I'm obsessed with anything technology related! On the weekends, you can find me playing around with my computers or fixing something around the house. Feel free to leave a comment if you want to get in touch.

Leave a Comment


Mobile data not working on your Android? Here’s 6 things to check

What is a DECT phone?