Firstly, the My Suica doesn't have an expiration date. Inactive cards can be re-activated by simply toping it up. And secondly, if ever you lose it, you can get a replacement at most train stations. Visit the Suica customer service counter or ticket machine and inform the staff that you've lost your card.

In 2026, a standard physical Suica card expires if it remains unused for 10 consecutive years. To check its status, you can tap it at any multi-functional ticket machine in a JR East station; if the card is "locked" due to inactivity, the machine will display an error or a message to see station staff. If the card is older than 10 years without use, the balance is technically forfeited, though staff can often issue a replacement or "reactivate" it if the timeframe is borderline. For the Welcome Suica (the red tourist card), the expiration is much shorter: it is only valid for 28 days from the date of purchase. You can find the exact expiration date for a Welcome Suica printed on the "Reference Paper" provided at the time of purchase. If you use a Mobile Suica on your phone, the app will clearly display the card status and any applicable expiration warnings directly on your home screen.