PayForTheBus.com
Know how to pay for the bus before you arrive.
Practical, cited guides for tourist bus systems: card, cash, tickets, boarding doors, airport buses, port buses, exact change and tap-off rules.

Buy your SITA Sud ticket before boarding (a tabacchi, bar, newsstand or the Unico Campania app), validate it on the bus, and consider the €10 COSTIERASITA 24-hour pass if you're visiting several towns.

Use one contactless card, Apple Pay, Google Pay or Oyster card for each traveller. Tap once on the yellow reader when boarding the bus and do not tap out.
Payment
Can you pay with card, Apple Pay, cash, exact change or a stored-value card?
Boarding
Do you board at the front, wave the bus down, tap off, or validate a ticket?
Arrival
Airport, port and station buses get first-class treatment because that is where travellers get stuck.
High-friction guides
We start with places where visitors are most likely to be confused: coast roads, island airports, ports and seasonal bus networks.
Amalfi
No, you can't tap a card or pay the driver on Amalfi Coast SITA Sud buses. Buy a ticket before boarding at a tobacconist, bar or newsstand showing the SITA SUD logo, or in the Unico Campania app, then validate it on board.
United KingdomLondon
London buses are one of the clearest cases: use contactless or Oyster, board at the front, and do not tap out on buses.
FranceParis
Paris buses do not work like London-style open-loop tap-to-pay for ordinary visitors: use Navigo Easy, the Île-de-France Mobilités app, an eligible phone ticket, or an SMS boarding ticket where available.
ItalyRome
Rome ATAC buses, trams, trolleybuses and metro support Tap & Go with contactless cards and NFC wallets; tap the reader and keep the same card/device for inspection.
United StatesNew York
New York MTA buses accept OMNY contactless cards, phone wallets and OMNY cards. Cash is still accepted on buses for now, but local buses require exact change in coins.
JapanTokyo
Tokyo Toei buses are best paid with a pre-charged IC card such as Suica or PASMO. Cash is accepted, but Toei says only coins and 1,000-yen bills are accepted for fare payment.