Code-based unlocking is the cheapest way to free a Samsung handset and the one with the most ways to go wrong. This page is the checklist we use when a customer says "the code did not work": every failure below has a specific cause, and most of them are diagnosable before you order anything.
An NCK is the network unlock code: a number derived from the IMEI that the operator's database can generate. MCK frees a sub-network (provider) lock, RGCK a regional lock and SPCK a service-provider lock. On a handset that still prompts for a code, entering the right one writes the unlock into the phone's non-volatile memory — it survives a factory reset and does not trip Knox.
The trouble is that "Samsung" is not one lock system. Since roughly 2020, most flagship and US carrier variants no longer prompt for a code at all: they are locked server-side, exactly like an iPhone, and must be released by the carrier. Sending a code order for one of those phones will fail every time, and no supplier can fix that.
Samsung does not publish unlock codes; they come from the operator that sold the handset. That is why the same model needs a Chile code in Chile, an Open Mexico code in Mexico and a Bell code in Canada — the database is the operator's, not the manufacturer's.
Samsung's own position is that carrier-locked devices must be released by the carrier, and the codes exist because many operators still generate them for older and mid-range stock.
Policies change without notice. The current wording is always on the carrier’s own page: Samsung support.
Every problem on this page is diagnosable before you buy a second code. The checks below cost cents and answer the two questions that decide everything: which region the handset belongs to, and whether it is a code lock at all. The code services themselves start at a couple of dollars and are refunded when no code can be generated for a covered model.
| Service | Price | What it does |
|---|---|---|
| Samsung IMEI check | Samsung device reports — model, region and lock state. | |
| Carrier and SIM lock check | Which network and region the handset belongs to, $0.03. | |
| Unlock code lookup | NCK / MCK / SPCK codes by brand and country. | |
| Samsung Canada Unlock Code NCK - Open Canada, Bell, Telus & More「Tested」 | $9 | Canada Open Canada NCK for Samsung. |
| Samsung Open Mexico Unlock Code - S22/S21/A series/Note 20 Series | $55 | Open Mexico RGCK + MCK for S22 / S21 / A / Note 20. |
Insert a SIM from another network and wait for the "SIM network unlock PIN" prompt, then type the NCK. If no prompt appears, the phone is either already unlocked or server-side locked.
In order of likelihood: wrong region, wrong code type (NCK vs MCK), a model the service does not cover, or a handset that is not code-locked at all.
No. It writes the unlock to NV memory; Knox and the warranty are untouched.
Usually five to ten before a hard lock. Enter the code once, carefully.
A code may still be generated, but the blacklist block stays and the phone will not get service. Run the blacklist check first.
Last checked 2026-10-28. Carrier rules are quoted from the operators’ own policy pages; if a rule has changed since, the carrier’s page wins.