Can i put old sim card in new phone? (Detailed explanation)

You bought a new phone and trying to figure out if indeed your old sim will work in the phone, I do understand you well enough cause there are things one needs to look into after buying a new phone.

So this is the case of a sim card, and asking can i put old sim card in new phone?

That’s the question of today, and I will explain everything you need to know about sim card and mobile phones especially when you purchase a brand new phone.

So let’s proceed to the question we have here, can i put my old sim card in my new phone.

Can i put old sim card in new phone

The simple answer is yes. You can put an old sim card in a new phone and it will definitely work as long as the old sim is of same size with the phone sim slot and the phone is not locked to a different carrier network. 

This is the first and foremost you need to look out for, is the new phone carrier locked, and if the sim card is compatible with the new phone in the case of micro sim and Nano sim.

So let’s take them one after the other with an explanation.

1. You cannot put the sim card if the phone is locked

If the new phone is locked to a specific network and the the sim card is from another network, definitely the sim card will not work in the new phone unless the new phone is fully unlocked.

Let me give you an example.

You have a sim card of AT&T network, and you bought a new phone which is locked to T-Mobile network. Sometimes you will see a sim card inside the phone, but you chose to use your old or main sim card.

So you removed your old AT&T sim card from your old phone, and insert it into your new phone which is locked to T-Mobile network. After you have powered the phone, you will see that it won’t show any network in the phone.

The reason for this is because the phone is locked to T-Mobile network and no any other network will work in the phone apart from T-Mobile network or sim card.

This is why most of these networks will put their SIM card into the locked phone because no another sim network will work in the phone except for their network.

In this situation you will need to unlock the phone, and unlocking the phone isn’t free and the cost will be high if you want to unlock the phone after one month or two months of buying the phone.

This is one major factor that answers the question of today, can i put old sim card in new phone.

However, if the new phone is unlocked, then you’re good to go because the old sim card will definitely work in the new phone.

■ You may want to read this I put my sim card in another phone and it won’t work

2. Put old sim card in new phone: if the sim card is compatible with the new phone

What do I mean by being compatible with the new phone?

What I mean by being compatible with the new phone is the case whereby you bought a Nano sim phone, and your old sim card is a micro sim card.

can i put old sim card in new phone

In this case they are not compatible with each other other, and there’s no way the old sim card will fit into the new phone unless you cut the old sim card or probably do a sim swap.

This is another major factor that answers the question of today, can i put old sim card in new phone. Once the sim card is not compatible with the new phone, it will not enter not to talk of working in the new phone.

■ You may want to read this Can you put any sim card into an unlocked phone

3. In the case of 5G network

You bought a new phone which is a 5G network phone, your old sim card doesn’t have or support the 5G network service, and you’re the type that mostly or sometimes make use the mobile data.

What the essence of using a 4G network sim card in a phone that has a 5G network?

Honestly it is a complete nonsense as long as you country has a 5G network. I don’t see need or the reason why you should use a 4G sim card in a 5G phone whereas you can get a 5G sim card around you or within your environment.

In this type of situation, I don’t recommend you using the old sim card in the new phone, instead you have to get a new 5G sim card and do a sim swap.

This is another factor that determines this question of “can i use my old sim card in my new phone”.

■ You may want to read this If I buy a new phone can I just switch SIM card

Now let me explain what sim swap is all about.

The Sim Swap

The sim swap simply means swapping your old sim to a new sim card, and it will still retain your mobile number.

This can only be done by your network. So if you have a micro sim card or you don’t a 5G network sim card, the only way of solving this problem is by swapping your old sim card to a new one.

You only need to contact your network provider and request that you want to swap your old sim card to a Nano sim or a 5G sim card. You will give them your mobile phone number and they will do the job for you.

This involves transferring your sim information or data to a new sim card and remember, it will retain your phone number.

SIM swap is free or a small token though it depends on one’s country or location. So instead of using an old SIM card in your new phone, you better do a sim swap and have a new sim card for your new phone.

So these are the factors that answer the question we have today, can i put old sim card in new phone. Just go get a new sim card and do a sim swap, and you’re good to go.

■ You may want to read this If i put my sim card in another phone will it save my contacts

Can i use my old sim card in my new phone

The answer is yes. You can use your old sim sim card in your new phone as long as the new phone is not locked to a specific network, and the sim card is compatible with the new phone.

This is same with the topic of the post, can i put old sim card in new phone. You don’t have any problem using your old sim card in your new phone as long as they are compatible with each other.

If the old sim is a 4G network and there’s no 5G in your location, and you have a fully unlocked phone, then there’s no need of getting a new sim card and doing a sim swap.

Kindly use the old sim card in your new phone cause definitely it will work. Immediately 5G network arrives in your location, then you can get a new sim card and do a sim swap.

Can I use my old SIM card in my new iPhone?

The answer is yes. You can use old sim card in your new iPhone if the sim is of same size with the new iPhone sim card slot. 

Talking about a new iPhone I will assume that it is a new iPhone that support the 5G network service. In this type of situation if your old sim card doesn’t support the 5G network service, then what’s the essence of using the old sim card in your new 5G iPhone. 

It doesn’t make sense at all to me unless in your environment there is no 5G network. 

However, if you have a 5G network service in your area and your new iPhone support 5G network service as well, please you need to upgrade your old sim card to a new 5G sim card. 

Mostly this is called a sim swap. 

You will swap all the data in your old sim card into your new sim card and it will transfer your old sim card phone number, contacts and other straight to your new 5G sim. Once you have done that, you can enjoy the full speed that comes with 5G services especially if you make use of mobile data for your internet activity on your iPhone.

Does it matter which SIM card I use?

It doesn’t necessarily matter which sim card you use on your cellphone. However, you may have to buy a 5G sim card if you happen to have a 5G phone and your area support 5G network service. 

Also, it does matter which sim card you use especially if your phone is not unlocked but rather locked to a specific network carrier. For example, your phone is locked to AT&T network and which no any other network sim card will work in the phone.

In this type of situation the sim card you will use in your phone matters because if you happen to buy a T-Mobile sim card, it won’t work in your locked phone. 

Remember that sim size also matters though right now we have a nano sim cards for the past six years and all phones are now nano sim card support. 

Related Questions 

Should I use old SIM card or new one?

I recommend you to use a new sim card if the old sim doesn’t support a 5G unless your phone is not a 5G phone. Again new sim card tends to have a high network frequency compared to old sim cards. 

Now you have seen the answer of can i put old sim card in new phone, you can now put your old sim card in your new phone.

About Kennedy

I'm Amaechi Uchenna by name, a mobile tech enthusiast who love writing articles about tips and tutorials especially relating to gadgets.

Leave a Comment