Rail
Rail has three payments. BTS Sukhumvit, Silom and the Gold Line: Rabbit. The FAQ lists a standard card at 200 baht (100 issue fee plus 100 stored value). A single ride is whatever the machine shows. Do not reuse an old guide's 120-baht day pass; if a day pass is on sale, the price is that day's notice. MRT Blue Line: BEM says that from 1 June 2026 the old MRT and MRT Plus stored-value cards stopped, replaced by EMV contactless bank cards. Rabbit's FAQ does not list the Blue Line. Airport Rail Link: another ticket. A government page says the Express is suspended; into the city you ride the all-stops City Line, and changing to the BTS at Phaya Thai is another fare. The Yellow and Pink lines are on Rabbit's list, which is not the same fact as the Blue Line.
船
Match boats to sights before you match them to a day pass. The orange express line runs Nonthaburi to Wat Ratchasingkhon, 19 baht flat on weekdays, and stops more often; Tha Chang, Tha Tien and Sathorn are on this river. Yellow is 24 baht, the red flag 33, with fewer stops. The green-yellow flag runs to the north end, 17/24/36 by section. The tourist boat is another company; flag, single fare and any day pass follow chaophrayatouristboat.com or the pier window. Tha Tien to Wat Arun is the short ferry. The Saen Saep boat is the canal at Pratunam and Phan Fa, paid in cash; at Pratunam you change boats toward the Golden Mount, and the fare moves with diesel, so pay what the boat charges that day. Rabbit's FAQ says the card can pay the Chao Phraya express boat. That is still not the Blue Line, not the airport line, and not the canal boat.