Samsung IMEI Check: Warranty, Region, Knox and Carrier Lock

A Samsung Galaxy can tell you a surprising amount about itself — if you know where to look. The model number reveals the region and chipset, a hidden code shows which carrier firmware it runs, and a quick IMEI check confirms warranty, origin and whether the phone has been reported lost.

Whether you’re buying a used Galaxy S, A or Z phone, or checking one you already own, this guide walks you through every check in order — from the dialer codes to the official records.

Step 1: Find the IMEI and serial number

Open the phone app and dial the universal IMEI code. The IMEI (or two, on dual-SIM models) appears immediately:

*#06#

You’ll often also see the serial number on the same screen. To cross-check, go to Settings › About phone, which lists the model name, model number, serial number and IMEI. On many models, tapping Status information (or Status) shows more detail.

The numbers in Settings, on the dialer and on the SIM tray or box should match. Validate the IMEI here before you run paid checks:

Step 2: Read the model number (it tells you the region)

Samsung model numbers look like SM-S928B or SM-A556E. The letters after the numbers matter:

Suffixes vary between product lines and years, so treat this as a guide, not a rule. A Samsung Info report confirms the exact model and the country it was sold in.

Step 3: Check the CSC code (carrier and region firmware)

The CSC (Consumer Software Customization) code shows which country or carrier firmware the phone runs. Find it in Settings › About phone › Software information › Service provider software version, or dial:

*#1234#

This shows the AP (software), CP (modem) and CSC versions. Common three-letter CSC codes include:

• XAA — US unlocked
• TMB — T-Mobile US · ATT — AT&T · VZW — Verizon
• BTU — UK unbranded · DBT — Germany · XEF — France

A carrier CSC doesn’t prove a phone is locked, but it tells you where it came from. If a “UK” phone shows TMB, ask questions.

Step 4: Check the warranty

Samsung warranty depends on the purchase date and the region the phone was sold in. Ways to check:

• Samsung Members app: open it and look under Support for device and warranty information.
• Samsung’s official support site: your local Samsung support page lets you register the device and see coverage.
• IMEI report: a Samsung Info S2 report shows warranty status, manufacture and sold-in details, which is useful when you’re buying and can’t log in to the seller’s account.

Remember: warranty service may be limited to the region where the phone was originally sold. A US model in Nigeria or the UK may not be covered locally.

Step 5: Knox — warranty bit and Knox Guard

“Knox” covers two very different things on a Samsung, and buyers often mix them up.

Knox warranty bit

Samsung phones contain a one-time fuse that trips if unofficial software is flashed (for example, rooting or a custom recovery). Once tripped, Knox-protected features such as Secure Folder and Samsung Pass can stop working, and it can affect warranty. You can see the status as “Knox Warranty Void” on the Download mode screen — 0x0 means untouched, 0x1 means tripped. It cannot be reset.

Knox Guard and device management

Knox Guard is a remote lock used by carriers, finance companies and businesses. A locked phone shows a payment or company message and restricts use. Like other management locks, only the company that applied it can release it. Run an MDM status check and read what an MDM lock is if you see a company name during setup.

Step 6: Carrier lock and blacklist status

A carrier-locked Galaxy shows a “SIM network unlock PIN” request or “SIM not supported” when you insert a SIM from another network. The quickest test is to try a different carrier’s SIM. For US carrier models, also check the original carrier’s unlock policy — see how to unlock a T-Mobile phone for the Device Unlock app many US Galaxies use.

Finally, check the phone hasn’t been reported lost or stolen with a GSMA blacklist check, and the USA blacklist / barred check for US models. Our Samsung IMEI check page brings these reports together.

Red flags on a used Galaxy

• The IMEI on *#06# doesn’t match Settings or the SIM tray — a sign of a board swap or tampering.
• The CSC or model suffix doesn’t match the seller’s story (a “UK phone” running US carrier firmware).
• Download mode shows Knox tripped on a phone sold as “never repaired”.
• A company name, payment message or “managed by your organization” appears during setup.
• The seller won’t let you remove the SIM, factory reset the phone or run a check.

Any one of these is a reason to slow down. Two or more is a reason to walk away.

Run your Samsung check

Checklist before you pay: IMEI matches in all places, model and CSC match the seller’s story, warranty is what was promised, Knox shows no management lock, and blacklist results are clean. For the full buying routine, see how to check a used Samsung before buying.