IMEI Check
Check Japanese Carrier Status and Blacklist by IMEI
Japan runs a domestic carrier blacklist that is separate from GSMA. A device can be clean worldwide and still blocked on every Japanese network, or the reverse.
Last reviewed 2026-10-26
Japan is the exception to the global blacklist model. Beyond the GSMA database, the three Japanese carriers maintain a shared domestic list, and a device flagged there will not register on any Japanese network regardless of its SIM lock state.
That makes a Japan-specific check essential for any device purchased in, or imported from, the Japanese market.
Domestic vs GSMA
- Clean domestically and clean on GSMA: the device is usable anywhere.
- Clean on GSMA but flagged in Japan: works abroad, blocks on Japanese networks.
- Flagged on GSMA but clean in Japan: blocks on Japanese networks too, since they also query GSMA.
- Both flagged: effectively unusable everywhere that enforces blacklists.
Note
Many buyers abroad deliberately accept a Japanese-flagged device because they never intend to use it in Japan. Decide based on the destination market, not on the flag alone.Which check to run
- Docomo / NTT: a dedicated blacklist check for iPhone and generic devices.
- au / KDDI: the UQ and au blacklist check.
- SoftBank and Y!mobile: a combined status check covering several SoftBank brands.
- Full coverage: the combined SoftBank au KDDI UQ Docomo status check, which reports across all three networks.
Ordering flow
- 1Confirm the carrier with a SIM lock check.
- 2Run the Japan status check for that carrier, or the combined one.
- 3If the device is flagged, decide whether the destination market enforces the flag.
- 4If it is clean, proceed to the unlock listing for that carrier.
Services used in this guide
These are the exact catalogue entries this guide refers to. Prices and turnaround are live.
Open the catalogueFrequently asked questions
Frequently asked questions
Does a Japanese blacklist follow the device abroad?
Not directly. Foreign networks query GSMA, which is a separate record. Domestic Japanese flags only block Japanese networks.
Can a Japanese blacklist be removed?
Generally no for theft reports. Some records raised for billing reasons can be addressed by the carrier that owns them.
Should I buy a Japanese-flagged phone for resale abroad?
Only if you disclose the flag to the buyer and price accordingly. Misrepresenting it is the fastest route to a dispute.
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