How to Check Clean ESN When Buying Your Next Used iPhone

Buying a used iPhone on eBay instead of a brand-new one is a good way to save a small fortune, especially if you don’t care about owning the latest and greatest model available. After each iPhone release, online marketplaces are flooded with used models from those who can’t stand the thought of being just one generation behind.

But not all used iPhone are made equal. Sellers who know what they’re doing will mention something called ESN, or Electronic Serial Numbers. If you don’t want to waste your money or give yourself a big headache, take a moment to read our article to learn everything you need to know about these pesky numbers.

What Is ESN

Electronic Serial Numbers are used to identify CDMA phones and authenticate subscribers to the networks. Unlike GSM phones, which use a SIM card and an IMEI number to do the same, CDMA phone usually have just an ESN. This standard is used predominantly in the United States, and it’s being gradually phased out in favor of a newer standard. This is happening because the number of available ESN identifiers is slowly running out.

What Is a Clean ESN and Blacklisted ESN

Carriers have huge databases of phones connected to their networks. If a phone gets stolen or someone forgets to pay a bill, they can remotely blacklist the associated ESN identifier from the network. It’s impossible to activate an iPhone with a blacklisted ESN on the network of the carrier that blacklisted it. In other words, if someone got the idea that Ting’s services shouldn’t cost any money and stopped paying his phone bills, you won’t be able to activate that person’s phone on Ting’s network. Clean ESN is the exact opposite of a blacklisted ESN. It means that the ESN identifier is ready for activation.

How to Check Clean ESN on iPhone

Being unable to activate your new iPhone is a huge problem, which is why you should always check whether the ESN of the phone you want to purchase is clean. Never ever pay any money to check ESN on iPhone. There are several ways how you can do it for free.

Major carriers such as Verizon, AT&T, and T-Mobile allow you to quickly check ESN from a web browser. The same functionality is also provided by many third-party sites, like Swappa, Ting, or CheckESNFree.

Alternatively, you can just go to the nearest store of your carrier and ask them to check the ESN identifier for you. This is particularly useful when you’re meeting someone in person and paying for the phone with cash.

What to Do with Bad ESN iPhone

If you somehow end up with an iPhone which has a bad ESN identifier—an identifier that’s banned on your network—there’re several things you can do. The most obvious one is to ask for a refund. All major online stores have refund policies and payment providers, such as PayPal, will almost always help you get your money back. Unfortunately, you probably won’t be able to get a refund from that shady pornstache-wearing seller from Craigslist.

If you want to use the device as you’ve originally intended, your best option is to flash it to another carrier, perhaps with AppleFlasher or a similar tool. This way, you’ll end up with a fully functional phone and a good story to tell your geeky friends.

Of course, not everyone has the time or energy or experience to mess around with carrier flashing or unlocking. In that case, you can still use the blacklisted device on Wi-Fi—perhaps as a gaming console or a very fancy e-book reader. And let’s not forget that you can always sell it for parts and get at least some of your money back.