How to inspect a used phone before you buy
Most used phone scams and bad buys come down to a few things: a stolen or blacklisted IMEI, a phone still locked to the seller's Apple ID or Google account, a worn battery, or hidden hardware faults. This checklist covers all of them in the order you'll meet them, from messaging the seller to handing over money. It takes about 10 minutes in person, and the free MxMob tests do most of the hardware checks for you.
The three checks that matter most
- IMEI: dial *#06# and check it on the CTIA Stolen Phone Checker. A blacklisted phone won't connect to US carriers.
- Activation Lock / FRP: if the seller's iCloud or Google account is still on the phone, you won't be able to use it after a reset. Always factory reset it together before paying.
- Battery health: below 80%, plan on a battery replacement ($50–$130 depending on the model).
Red flags: walk away if…
- the seller won't let you dial *#06# or check Settings;
- the phone won't factory reset in front of you, or asks for someone else's password afterwards;
- the back or screen is bulging;
- the model number or graphics chip doesn't match the model advertised;
- the seller pushes for payment by gift card, wire transfer or crypto.
Buying on Facebook Marketplace, Craigslist or OfferUp
Meet in daylight at a public place with Wi-Fi or good signal, ideally a police station safe exchange zone or the seller's carrier store, which can confirm the phone isn't blacklisted. Bring a SIM card, a charging cable and a pair of earbuds so you can test calls, charging and audio. Open mxmob.com/check on the phone itself to run every hardware test in about 5 minutes, then save the report.
Frequently asked questions
What should I check before buying a used phone?
Check the IMEI is not blacklisted, make sure the seller has removed their Apple ID or Google account, confirm the carrier lock status, check battery health is 80% or more, and test the screen, cameras, speakers, charging and buttons. A full online diagnostic covers the hardware in about 5 minutes.
How do I check if a used phone is stolen?
Dial *#06# to get the IMEI and enter it in the free CTIA Stolen Phone Checker at stolenphonechecker.org. Carriers such as T-Mobile, AT&T and Verizon can also confirm whether an IMEI is blacklisted.
How do I know if a used iPhone is iCloud locked?
Open Settings and check that no Apple ID name appears at the top, and that Find My is off. After a factory reset, the phone must reach the Hello screen and set up without asking for the previous owner's Apple ID password.