International Unlocked vs. US Factory Unlocked Cell Phones

Here’s everything about the difference between international unlocked and US factory unlocked cell phones:

International unlocked phones and US factory unlocked phones are essentially the same but may differ in the frequency bands that signals are transmitted upon.

Thus, if you want to use your phone overseas, you will need to check if it can operate on GSM bands, specifically, 850 MHz, 900 MHz, 1800 MHz, or 1900 MHz.

So if you want all about how internationally unlocked and US factory unlocked cell phones work exactly, then this article is for you.

Let’s get right into it!

International Unlocked vs. US Factory Unlocked Cell Phones.

What Is the Difference Between International Unlocked and US Factory Unlocked Cell Phones?

Testing smartphone and smart watch inside gadget area of a mall.

Unlocked smartphones enable their owners to use the phone with any mobile carrier they like and anywhere they go. 

All you need to do is get a SIM card from a cellular carrier and make sure it fits your phone. 

Insert the new SIM card into your phone, then start using your phone and data on that carrier.

But if you want to make a trip overseas, you might want to get an international unlocked phone for use while you’re visiting.

An unlocked international phone and a US factory unlocked phone are similar in many ways but different in others.

You can use both types of phones on cellular networks in the US, and you can get a SIM card for both types when traveling overseas.

Not sure if you want an unlocked smartphone for the US only or international travel?

Read on to learn more about the difference between the two types of phones and the reasons why you would want to buy one type of phone over the other.

What Is a Factory Unlocked Smartphone?

An unlocked smartphone is one that’s not locked to any one carrier.

These phones are usually available directly from the manufacturer and are known as factory unlocked phone.

For example, you want to buy an unlocked iPhone and use it on your carrier of choice.

You’ll need to buy the phone directly from Apple, either in a store or online, and decline the purchase of a SIM card for a specific carrier.

Before you buy the phone, look to make sure that it’s a factory unlocked phone.

The difference between a factory unlocked phone versus a carrier locked phone is the cellular network it can operate on.

In the US, there are two cellular standards known as CDMA (Code-Division Multiple Access) and GSM (Global System for Mobile Communications). 

A carrier-locked phone can only operate on the cellular standard that the carrier uses.

In contrast, an unlocked smartphone can operate on either CDMA or GSM networks.

GSM is shorthand for Global Standard for Mobiles, and CDMA is short for Code Division Multiple Access.

GSM is in use everywhere in the world, while CDMA is mostly used in America.

The reason why a factory unlocked smartphone can operate on either network comes down to the antennas.

A carrier-locked smartphone may have only one antenna for that specific carrier, whereas a factory unlocked smartphone will have antennas for GSM and CDMA.

What Is an International Unlocked Smartphone?

You may have come across smartphones that state the fact that they’re international on their listings.

This is due to the fact the phones are intended to work in countries other than the US Manufacturers such as LG and Samsung make phones for just about every possible market and tweak them to work in a given country.

International phones frequently use the same model numbers around the world and are made to the same specifications.

They can be used out of the box in the US as long as the cellular provider is using a GSM network.

An international unlocked smartphone is essentially the same as a US factory unlocked smartphone with a slight difference: bands.

That is the frequency bands that cellular signals are transmitted upon. 

If you want to use your phone overseas, you need to check that it can operate on the following bands in the GSM standard:

  • 850 MHz
  • 900 MHz
  • 1800 MHz
  • 1900 MHz

You can find this information online or in the manual that came with your phone, or look online if you don’t happen to have it handy.

Chances are good that your phone will work on any of these bands in other countries.

This is because phone manufacturers tend to put all relevant radio circuitry in their phones to make it easier to sell them anywhere.

International Unlocked vs. US Factory Unlocked Smartphone

As I mentioned previously, there’s not a lot of difference between an international locked smartphone and a US factory unlocked smartphone. 

However, it’s good to know the differences between the two before you decide on which phone to buy or get unlocked.

So here’s a look at the differences between both types of phones:

A US factory unlocked smartphone can:

  • Be used on any carrier in the United States
  • Comes with a warranty
  • Sold directly by the factory
  • Used with any compatible network in the world

An international unlocked smartphone:

  • Can be used in any country around the world with a GSM network
  • Does not come with a warranty
  • Typically sold by third-party vendors
  • May have some minor variations from the US version of the same model

Can I Use an International Unlocked Smartphone in the US?

Yes, you can use an international unlocked smartphone in the US as long as it can operate on the GSM network.

However, you’re restricted to using one of two mobile operators with an international unlocked smartphone.

It’s worth noting that there are sometimes subtle differences between an international unlocked smartphone and a US unlocked phone of the same model. 

An international model may have trouble maintaining a connection to the network due to not having the circuitry for operating on a specific band.

Sometimes it happens that the phone’s software for connecting to a specific band wasn’t switched on at the factory.

Do the research before you go ahead and buy a less expensive version of a US smartphone.

Others who have gone this route will most likely share their experiences and provide a walk-through that shows you how to properly connect an international unlocked smartphone to a US cellular network.

How Do I Find Out Which Type of Cellular Network My Smartphone Works On?

There are a few ways to find out which network your phone is compatible with.

One option is to use a website that requires a couple of inputs, then return the types of networks your phone will operate on. Another is to call your carrier or go to their website to find out which technology is used.

If you’re not having luck with either of those options, go into your phone’s Settings and look for About Phone.

The information you need is usually next to the Model Number

In the event the phone doesn’t tell you if it’s CDMA or GSM, a search engine query can help you quickly determine which network your phone works on.

Can I Get My Current Smartphone Unlocked?

You may not be able to get your current smartphone unlocked by your carrier, especially if you bought it at their store.

Carriers frequently sell phones that are locked into their network, then make it difficult to get them released unless you’ve paid off the phone.

Are you paying off your phone?

It might not be worth fighting with your cell phone carrier to unlock your phone.

Buying a burner phone that can operate internationally is a better alternative. You maintain connectivity with home, get your emails, and you can dispose of the SIM card when you leave the country.

If something happens to that burner phone while you’re on vacation, you won’t be out a lot of money. You’ll also be less inconvenienced because you still have your personal phone at home.

However, if you want to unlock your phone for international travel, you can go to your carrier for an unlock code.

All cell phone carriers have different policies for issuing a code that unlocks your phone.

If you can’t get your smartphone unlocked in the US, you can try an unlock store in your destination country.

These types of stores are found all over the world and will get your phone unlocked for you.


  • Theresa McDonough

    Tech entrepreneur and founder of Tech Medic, who has become a prominent advocate for the Right to Repair movement. She has testified before the US Federal Trade Commission and been featured on CBS Sunday Morning, helping influence change within the tech industry.