Yes, standard Japanese Suica cards (the green IC cards used for transit) do expire, but they have an incredibly long lifespan: they remain valid for 10 years from the date of last use. If you visit Japan and don't return for over a decade, the card will become void, and any remaining balance is forfeited (though you can sometimes get a refund for the 500 yen deposit at a JR ticket office if the card is still physically readable). However, if you have a Welcome Suica (the red tourist version), it has a very different rule: it is only valid for 28 days from the date of first use and cannot be refunded. In 2026, many travelers have switched to "Mobile Suica" on their iPhones or Androids, which generally does not expire as long as the digital wallet remains active, though the same 10-year inactivity rule still technically applies to the underlying account.