Before You Buy a Used Phone, Look Up Its 15-Digit IMEI: Lost or Stolen Devices Cannot Be Activated, and the Same Number Shows 25% Plan Discount Eligibility
When you buy a used phone on a secondhand marketplace, the first things you look at are the price and the condition. But even if the seller's photos look fine, a device that has been reported lost or stolen cannot be activated. There is a free lookup that screens for this, and the key is the 15-digit identifier on every phone, the IMEI. This article sets out the steps based on the official guidance of the Korea Association of Information & Telecommunication (KAIT) and Smart Choice.
The IMEI is the unique number of the device
The IMEI is the device identification number attached to each phone. A phone number or a SIM card can be swapped, but this number stays with the device, so it is the reference point when judging whether a phone was lost or stolen. It is different from a serial number with a similar-sounding name, so you must use the digits labeled IMEI.
How to check the IMEI
Smart Choice describes three ways. First, dial *#06# on the phone keypad and the number appears on screen. Second, on a Galaxy go to Settings, About phone, Status; on an iPhone go to Settings, General, About. Third, check the label on the back of the device or on the box. Depending on the device, more than one IMEI may be shown, so write down every number that appears. If a seller offers only to text you the number, it is safer to meet, ask them to dial *#06# in front of you, and compare the result with the number on the box or label.
The lost-or-stolen lookup is on the KAIT device self-purchase site
The lookup is the lost and stolen device inquiry on the mobile phone self-purchase (jageupje) site run by KAIT. You agree to the collection of personal information, enter the IMEI, and the site states that the IMEI is used only for the lookup and discarded after processing. The lookup is free. However, automated lookup programs and bulk lookups are not allowed, and abnormal access may be blocked. Inquiries go to KAIT at 1577-4563 or imei@kait.or.kr.
A lost or stolen device cannot be activated
The Smart Choice notice says that lost or stolen devices cannot be activated and recommends a separate lookup to check. If you do not check before the deal, you learn that it will not activate only after you have sent the money. If you have already paid, see why a payment freeze fails in secondhand fraud and the reporting steps.
When the lookup flags the phone or the numbers do not match
What follows is not statute but a response we recommend. If the phone is listed as lost or stolen, stop the deal; if you have already paid, ask the seller for a refund and keep the chat and transfer records. A seller who will not give the number or is reluctant to show it in person, or a number on the screen that differs from the box or label, are each a reason to postpone. If you suspect fraud, report it to the police and also use the platform's reporting function. The more a seller rushes you to pay quickly, the more one lookup is worth.
The result is for reference only
The KAIT inquiry screen states that the service exists to check whether a phone is lost or stolen and should be used for reference only. A clean result is therefore not a guarantee that the device is safe. Treat the lookup as one step in checking a deal, and also keep a record of the seller's identity and the transaction.
The same number also shows 25% plan discount eligibility
The Smart Choice device identification lookup also shows whether a device is eligible for the 25% plan discount (selective contract discount). The notice adds that this discount applies only to the three major carriers, SKT, KT and LG U+, and that MVNO (budget carrier) users are not covered. The structure of the discount itself is covered in the article on how the 25% discount ends when the contract ends.
Before and after buying: the order of steps
Some questions for the seller are worth setting in advance. The three we recommend are whether the phone was bought in the seller's own name, whether the box and purchase record exist, and whether the seller can show the IMEI in person. If any answer is vague, it is better to wait, however cheap the price.
First, meet and read the IMEI yourself with *#06# and compare it with the box and label. Second, enter those 15 digits into the KAIT lost and stolen device lookup and, if needed, check 25% discount eligibility on Smart Choice. Third, after buying, confirm that no account of the previous owner remains; Google and Apple account issues are covered in the order for resetting a used phone. Fourth, if you plan to port your number after activating it, also know about the three-month activation limit. This article is general information and does not replace a legal judgment on any individual deal. Methods and screens may change, so confirm specifics with KAIT and your carrier's official channels.
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