Buying a used phone can save you ₹10,000 or more, and Diwali is when a lot of people sell their old one after upgrading. The safe way to do it takes about 15 minutes: check the IMEI with the government’s free SMS service, make sure no one else’s account is still locked to the phone, then look at the battery and bill.
Skip one of those and you could pay for a phone that’s blacklisted or simply won’t switch on after a reset. The lock that catches most buyers is in section 3, and the seller usually doesn’t even know it’s there.
⚡ Key takeaways
- Dial *#06# for the IMEI, then SMS “KYM <15-digit IMEI>” to 14422. If the result says blacklisted, duplicate or already in use, walk away.
- On an iPhone, don’t pay if you see “iPhone Locked to Owner” or a passcode screen. Apple says the phone must be erased first.
- On Android, the seller must remove their Google account before the reset, or the phone can stay locked to them.
- Check battery health and warranty, and ask for the original bill. No bill on a nearly new phone is a red flag.
- This guide is for buying from a friend, OLX-style listing or local shop. Refurbished phones from a big store come with their own warranty rules.
Why Buying a Used Phone Needs a Checklist
A used phone looks the same whether it’s honest or stolen. The screen lights up, the camera works, the seller seems friendly. The problems show up later, when your SIM stops working or the phone asks for someone else’s password.
India has a government system built for exactly this. The Department of Telecommunications runs Sanchar Saathi, and one of its citizen services is called “Know Genuineness of Your Mobile Handset”. Phones reported lost or stolen can be blocked through its CEIR portal, so a stolen phone may stop working on Indian networks.
That’s good news for owners. For buyers, it means a phone that’s cheap for a reason can turn into a paperweight a week after you pay.

Check 1: The IMEI, With One Free SMS
Every phone has a 15-digit IMEI number. Dual-SIM phones have two.
How to do it
- Dial \*#06# on the phone you’re buying. The IMEI shows on screen.
- Match it with the number printed on the box and the bill. All three should be the same.
- From any phone, send an SMS: KYM followed by the 15-digit IMEI, to 14422. Sanchar Saathi also has a web form and app for the same check.
The official service says to avoid buying if the status comes back as blacklisted, duplicate or already in use. A phone with a valid, matching IMEI is a good start. It doesn’t prove the seller owns it, though, so don’t stop here.
💡 Pro tip
Do the SMS check from your own phone, standing next to the seller. If they get uneasy about it, you have your answer.
Also readCheck Your Phone’s Battery Health in 2 Minutes (Android, iPhone) Check 2 and 3: The Locks That Brick Phones After a Reset
This is the part most buyers miss. Phones have anti-theft locks tied to the owner’s account, and a factory reset doesn’t remove them.
On an iPhone: Activation Lock
Apple’s guide to buying a used iPhone is blunt. If you see the “iPhone Locked to Owner” screen, don’t take the phone. If a passcode lock screen or the home screen appears, the seller still needs to erase it.
If setup asks for the previous owner’s Apple Account, the phone is still linked to them. Hand it back so they can sign in, or ask them to remove it from their account. The phone is ready for you only when it shows the “Hello” screen.
On Android: Google’s factory reset protection
Android has a similar lock. Google’s Android help page says that after a reset on a protected device, you must enter the old screen lock or the Google Account password. If you can’t, Google says you won’t be able to use the device at all.
So ask the seller to remove their Google account first (Settings, then Accounts or Passwords and accounts), then reset the phone in front of you. Samsung phones may also have a Samsung account lock, so ask them to sign out of that too.
⚠️ Watch out
“I’ll send you the password later” is not good enough. Once you’ve paid and left, a seller has no reason to answer your calls. Get the phone to the setup screen before money moves.
Check 4: Battery Health, Body and Basics
An old battery is the most common hidden cost. A replacement can be expensive on flagships, so check it before you agree on a price.
| What to check | How | Walk away if |
|---|---|---|
| Battery health | iPhone: Settings, Battery, Battery Health. Android: see our guide below | Under about 80%, unless the price reflects it |
| Screen | Open a white page and a black page at full brightness | Lines, pink patches or dead spots |
| Cameras | Take a photo with every lens, front and back | Blur, spots or a lens that won’t switch |
| Charging port | Plug in your own charger | Loose fit or no charging |
| Speakers and mic | Make a short call and record a voice note | Crackling or no sound |
| Buttons and Face ID or fingerprint | Press each button, set up unlock | Any button stuck or biometrics fail |
| Water damage | Look for rust in the SIM tray slot | Corrosion or a bent SIM tray |

Our battery health guide has step-by-step paths for iPhone, Pixel and Samsung, plus what the 80% figure actually means.
Check 5 and 6: Bill, Box and Warranty
Ask for the original invoice
A real owner of a one-year-old phone usually has the bill in their email or on the Flipkart or Amazon app. Check that the IMEI on the bill matches the phone. A bill also helps you if you ever need a warranty claim or have to prove where the phone came from.
No bill isn’t always a scam. Older phones lose paperwork. But on a phone that’s only a few months old, missing papers is worth a lower price or a polite no.
Check the warranty yourself
For iPhones, Apple’s check coverage page shows a device’s coverage from its serial number. For Android phones, the brand’s support site or service centre can confirm warranty from the IMEI or serial number. Don’t rely only on what the seller says.
Check 7: Pay Safely and Get It in Writing
Even after every check, keep the payment clean.
- Meet in a public place with Wi-Fi or good network, so you can run the KYM SMS and the setup screen there.
- Pay by UPI or bank transfer to an account in the seller’s name, so there’s a record. If the name on UPI doesn’t match the person, ask why.
- Write a short sale note: date, phone model, IMEI, price, both names and phone numbers, signed by both of you. A photo of the seller’s ID with their consent helps too.
- Put in your SIM and make one call before you leave.
- Change the phone’s settings to yours: new screen lock, your Google or Apple account, and turn on Find My Device or Find My.
If something goes wrong later, the sale note and UPI record are your proof. If the phone was stolen and the real owner gets it blocked, those records matter a lot.

New, Open-Box or Used: Which Should You Buy?
A used phone isn’t always the cheapest option once you add a battery swap or repairs. During festive sales, a new mid-range phone with bank offers can cost close to a two-year-old flagship. Use our fake discount check before you assume a sale price is real.
If you buy new online
On Flipkart, open-box delivery lets the agent open the sealed box in front of you before you share the OTP. Owners on TechEnclave’s forum advise matching the box IMEI with the phone and checking it switches on before giving the OTP. They also report that the check covers physical condition, not hidden faults.
✅ Our verdict
A used phone is worth it if the IMEI is clean, the locks are gone and the setup screen shows up, and the price leaves room for a battery if needed. Walk away from any seller who won’t let you do the KYM check or reset the phone in front of you. A ₹3,000 saving isn’t worth a blocked phone.
Frequently Asked Questions
How do I check if a used phone is stolen in India?
Dial *#06# to get the IMEI and send “KYM <IMEI>” to 14422, or use the Sanchar Saathi website or app. Avoid the phone if the status is blacklisted, duplicate or already in use. Also match the IMEI with the box and bill.
What is the KYM number for IMEI check?
The number is 14422. Type KYM, then the 15-digit IMEI, and send it as an SMS. The service is free and run by the Department of Telecommunications through Sanchar Saathi.
Can a used iPhone be locked to the old owner?
Yes. Activation Lock stays on until the owner removes the phone from their Apple Account. Apple advises not to take a used iPhone that shows “iPhone Locked to Owner” or still has a passcode screen.
Is it safe to buy a used phone without a bill?
It’s riskier. A bill proves where the phone came from and helps with warranty. For older phones, a clean IMEI check, a proper reset and a signed sale note reduce the risk, but get a better price.
What battery health is okay on a used phone?
Many buyers treat about 80% as the line where a battery feels noticeably weaker. Below that, budget for a replacement and negotiate the price down.
The Bottom Line
Buying a used phone is smart money if you check before you pay: IMEI by SMS, locks removed, setup screen showing, battery and bill in order. It takes 15 minutes and saves you from the worst kind of bargain.
Before your next sale purchase, also read how to spot Diwali sale scams, because fake “used iPhone” deals are a favourite trick.
Keep reading
Read nextCheck Your Phone’s Battery Health in 2 Minutes (Android, iPhone)
Read nextDiwali Sale Scams: 7 Fake Offers to Spot Before You Pay
Read next15 Smartphone Privacy Settings You Probably Never ChangedSources
- Sanchar Saathi (DoT): Know Genuineness of Your Mobile Handset, KYM to 14422
- CEIR (DoT): block lost or stolen mobile handset
- Apple Support: what to do before you buy a used iPhone or iPad
- Google Android Help: factory reset protection
- Apple: check device coverage
- TechEnclave forum: checks before accepting Flipkart open-box delivery