You’ve probably heard about the My Number card since arriving in Japan. Maybe someone at your ward office mentioned it. Maybe your employer asked about it. Here’s what it actually is and whether you really need one.
What Is My Number?
My Number (マイナンバー) is Japan’s national ID system. Every person living in Japan — including foreigners — gets a unique 12-digit number.
You received your My Number in the mail shortly after registering your address in Japan. It came in a thin envelope, probably looked unimportant, and hopefully you didn’t throw it out.
My Number vs My Number Card — They’re Not the Same Thing
This trips a lot of people up. They’re two different things:
| My Number | My Number Card | |
|---|---|---|
| What it is | A 12-digit ID number | A physical IC card |
| Required? | Yes — everyone has one | No — optional |
| How you get it | Assigned automatically | You apply for it |
You already have the number. The card is optional — but increasingly useful.
What the My Number Card Is Actually Used For
The card is becoming more important every year in Japan. Right now it’s useful for:
- Proof of identity — accepted everywhere instead of your residence card
- Health insurance card — many hospitals now use it instead of the separate insurance card
- Tax filing — required for e-Tax (online tax filing)
- Bank account verification — some banks require it
- Government services — access to the Myna Portal (online government services)
- COVID-19 vaccination record — linked automatically
Honestly, the list keeps growing. More services are tying into it every year.
Should Foreigners Get It?
Yes. Get it.
It’s technically optional, but it makes daily life noticeably easier and that’s only going to be more true over time. If you’re staying in Japan for more than a year, just apply for it.
How to Apply for the My Number Card
Method 1 — Online (Easiest)
- Find your My Number notification letter (the one sent by post when you registered your address)
- Go to mynumber.go.jp
- Take a photo of yourself (selfie) that meets the requirements:
- Plain white or light background
- Face clearly visible, no glasses
- No hat
- Upload via the QR code on your notification letter
- Wait 1–2 months
Method 2 — At City Hall
- Go to your local City Hall (市役所)
- Bring: residence card, passport
- Fill in the application form — staff will help you through it
- Come back in 1–2 months to collect your card when you receive the postcard notification
What If You Lost Your Notification Letter?
Don’t panic. Visit City Hall and ask for a reissue. Bring your residence card and passport. It’s a quick process.
Is the My Number Card the Same as the Residence Card?
No. These are two completely different cards:
| Residence Card (在留カード) | My Number Card (マイナンバーカード) | |
|---|---|---|
| Issued by | Immigration | City Hall |
| Required? | Yes — mandatory for foreigners | No — optional |
| Shows visa status? | Yes | No |
| Used as ID? | Yes | Yes |
You always need your residence card — that one’s mandatory. The My Number Card is an extra, increasingly useful ID card on top of that.
Summary
- Everyone in Japan has a My Number — it’s assigned automatically
- The My Number Card is optional but makes life easier
- Apply online or at City Hall — takes about 1–2 months
- Recommended: get it, especially if you’re planning to stay long-term