Galaxy S8 with SIM cardsSource: Android Central

Best answer: The easiest way to see if your phone is unlocked is to try another SIM card in it. You can also call the carrier you purchased it from to check the status and request an unlock.

Where did you buy it, and how?

Carrier-locked phones are limited to using a SIM from just one carrier. This means that if you want to change carriers, you'll need to make sure your phone is unlocked or get ready to buy a new one. The good news is that if you've paid off your phone, you can get it unlocked and bring it to another carrier.

If you bought your phone from a carrier, the first thing to do is make sure it's paid off. If you were paying it off over a series of payments, you'd need to make sure you have paid the full balance. Once it's paid off, it will either unlock automatically, or you can request an unlock from the carrier. If you're switching to a new carrier, make sure to get your phone unlocked before you leave your old carrier. You can still get your phone unlocked down the line, but it can take a lot longer and may require account information you don't have handy.

If you bought your phone from Amazon or another online retailer, the phone would be listed as unlocked or carrier-specific. Be sure to choose the unlocked version for your region. International models will work with U.S. carriers, but you may not have access to all carrier bands.

Of course, if you bought your phone directly from the manufacturer and listed it as unlocked, it would be. All phones sold directly from Google are unlocked, and many phones from other manufacturers like Samsung, OnePlus, and even Apple are sold directly, and SIM unlocked.

For the rest of the phones out there, there's really only one fool-proof way to check: Try it.

How to check if your phone is unlocked

Visible Swap Old HuaweiSource: Samuel Contreras / Android Central

You'll see websites that claim you can check if your phone is unlocked online. While that might be true, these services cost money and are often incorrect. I'll come right out and say it: don't bother.

Instead, you can call your carrier or the carrier or MVNO you're thinking of switching to. Companies keep a database of IMEI numbers that says which phones are compatible, unlocked, or blacklisted. You might not have any luck here, though, because the person answering the phone might not be able to give you that information — they either don't have access to it or aren't allowed to tell you over the phone. It's worth a try if you don't have access to a SIM card from a different company, though.

Skipping all of that, the easiest way to find out if your phone is unlocked is to just put in a SIM card from another carrier. And it doesn't have to be a SIM card connected to an active account — the phone will try to initiate a connection with any SIM card in place. Some carriers like Google Fi will even send you a SIM for free, and you aren't charged anything until you activate the card. The process is as follows:

  1. Make a phone call using your current SIM card, if possible. This is to check that the phone is working properly. (Call your mom and tell her hello; she'll appreciate it.)
  2. Shut off the phone and remove the SIM card. Look in the manual or online if you're not sure how to do this, and if you need a SIM card removal tool, a paperclip usually works fine. You may also want to give it a SIM PIN code first, so no one can steal and use your old SIM card.
  3. Put the new SIM card in your phone and power it back on.
  4. If you're greeted with a dialog box telling you to enter a SIM unlock code, your phone is SIM locked to the carrier it was originally purchased from.
  5. If you don't see an unlock code prompt, check that it says you have service if you used a valid SIM card. If you do, your phone is probably unlocked. Try making another phone call. (Mom won't mind two calls on the same day.)

If you can't call using the new SIM card, you'll probably get a recorded message with some error code. You can jot down the code and check online to see why the call can't be completed so you know if it's because of a SIM lock or because of incompatible hardware. Having a wholly incompatible phone with another network is unlikely nowadays, but it's worth checking.

If you don't have access to another SIM card, you can also take your phone into a carrier store and tell them you're thinking of switching carriers and want to check if it's unlocked. Don't feel bad about telling a little white lie to a carrier — they tell them to us all of the time. They should be able to help you put in a SIM card and check.

If your phone is SIM-locked, don't fret. Carriers are required to SIM unlock your phone provided it has been paid for in full, and your account is in good standing. Each carrier has slightly different rules regarding how long you have to own the phone and how long your account has to be open, but you can give customer service a call, and they'll help you out. Here's some information for the major U.S. carriers:

Do you need an unlocked phone?

Most smartphone owners ask how to check if their phone is unlocked because they plan to switch carriers. You may or may not have heard of MVNO carriers, which are gaining popularity as a cheaper alternative for service. We think that's great because having even more choices can't be a bad thing. And even if you go with one of the "big" carriers, having the ability to switch whenever you want puts the power in your hands.

But no matter which of the best cell phone plans you want to adopt, you'll need to make sure you have a SIM-unlocked phone first. That means you can use a SIM card from any company, so long as the hardware is compatible with the network, with no restrictions.

Most of the best Android phones are available unlocked, but if you bought it directly from a carrier, you might not know how that affects your options. Here's what you need to know to check if your phone is unlocked or what to do if it isn't unlocked.

Switching to an MVNO

Now that you know how to check if your phone is unlocked, your next question should be what to do with your newly freed phone. There are several important considerations you should make when switching to an MNVO, including checking if your phone works with MNVOs.

If you've already decided that's your path forward, then your next step is choosing an MNVO. Since your phone may be restricted to a single provider, we have round-ups on the best Verizon MNVOs, best T-Mobile MNVOs, and all AT&T MNVOs to help you decide.

Our pick

Samsung Galaxy S21 Render Phantom Violet Front Official

Samsung Galaxy S21

One of the best Android phones today is also available unlocked.

The Galaxy S21 is one of the best Android phones you can get with fast hardware and some of the best cameras in the business. You also get support for 5G on all major carriers with mmWave.

Unlocked for less

Pixel 4a Barely Blue Render

Google Pixel 4a

A great unlocked phone with an exceptional camera for less money.

Available unlocked by default, the Pixel 4a has a premium camera, great battery life, and three years of guaranteed software updates for a shockingly low price. It lacks some of the Pixel 5's features, but the discount makes up for it.

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