How many people can use one Istanbulkart transit card in Istanbul?

One card is enough for a whole group — you don't need to buy a separate card per person. The card itself costs 100 lira; you tap it multiple times for each passenger.

It's worth checking whether the Havaist airport bus (line 9) accepts direct bank card payment, without needing an Istanbulkart.

Topping up an Istanbulkart with a foreign bank card often fails — many travelers report payment errors when trying to recharge online.

One Istanbulkart can definitely cover 3 passengers, possibly 4 — just tap the card multiple times at the turnstile, once per person.

According to official rules, one Istanbulkart can pay for a maximum of 2 passengers per trip. For 3 or more people, a second card is needed.

For a group of 8, note that refunds when returning the card are issued to only one person. It may be more practical to buy multiple cards.

There is a maximum balance limit on the Istanbulkart — if you try to top it up beyond that limit, the transaction will be declined.

One Istanbulkart cannot pay for 4 people in a single tap — the card is limited to a set number of passengers per transaction.