Ticket gates return an error when the scan encounters more than one compatible card. Although it is intended that each person have only one Suica, many people have more than one.

No, you cannot use a single Suica card for multiple people at a ticket gate. The Japanese transit system is "entry-exit" based, meaning the card must be tapped at the start of the journey and again at the end to calculate the correct fare. If you were to tap a card and hand it back to someone else, the system would register an "incomplete journey" and lock the card. Every traveler, including children over the age of six, must have their own individual Suica, Pasmo, or other IC card. In 2026, for those traveling as a group, the "Welcome Suica" or "Pasmo Passport" are the best options for tourists, as they can be purchased quickly at airports. The only exception to the "one person, one card" rule is for retail purchases; you can use your Suica card to pay for multiple items or even multiple meals at a restaurant or convenience store, provided the balance is high enough. For train travel, however, the rule is strictly one card per passenger to ensure the automated gates can correctly track and bill the thousands of individual journeys occurring every minute.