Can you pay for Havas airport bus in Istanbul with a transport card or only cash?

Practical tip: buy an Istanbulkart with cash, as bank-card payments at the machine often fail, including with both Turkish and foreign cards.

Updated Havaist payment information: tap either an Istanbulkart or a bank card when boarding; cash is not accepted on the bus. An Istanbulkart can be bought from a Biletmatik machine for 200 TL with cash or a bank card and topped up there or at platform ticket counters.

You can top up your Istanbulkart at the Havas ticket counter (e.g. 1000 lira) and then use the same card for two passengers, similar to how shared transit cards work in other cities.

Havas buses only accept the Istanbulkart; cash payments are not accepted. This can be inconvenient for newly arrived travelers who don't yet have a card.

A budget-friendly alternative to Havas: ride to Kabataş and transfer to Şehir Hatları municipal ferries. The total cost is roughly the same, and the ferries are considered more reliable — they also accept the Istanbulkart.