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My Numberマイナンバー·mai nambā

Your 12-digit national ID number, sent to you by mail after you register your address.

Not verified yet

Drafted from general knowledge of national procedure. Not yet checked against the official source — confirm details with your city hall before relying on them.

Why it matters

You will be asked for this number by your employer, your bank, and the tax office. You do not apply for it — it is issued automatically once you are registered — but you do need to not lose the paper it arrives on.

Deadline
No legal deadline
Cost
Free
Time
Arrives by mail — no action needed

Do these first

  1. 1Move-in Notification 転入届

What to bring

Nothing to bring — this one comes to you.

How it goes

  1. 1

    Wait for the mail

    A notification arrives at your registered address, typically within a few weeks of registering. Make sure your name is on your mailbox or the postal service may return it.

  2. 2

    Store it somewhere you will find it again

    Your employer will ask for this number, usually on your first day or at your first tax filing.