In reply to your other question, Kpurden, the taxi fare from Kos airport to Mastichari (7km) is 13-15 EUR. (From the airport to Kos town it would be at least twice that amount; the distance is about 35km.)

Ferries: Yes, the last one does wait for the late flights of the day. The last ferry is always the fast ferry, as Herre mentions (anekalymnou.gr). According to the ferry company, that’s the very reason why their schedule changes so frequently (to accommodate the flights).

Make sure to check the timetable close to your travel date. The timetable changes often! We have both ferry schedules here http://climbkalymnos.com/wp-content/uploads/Kos_Ferries_May19_23_2017.pdf, but sometimes we miss the latest changes, so always check the individual sites of the ferry companies as well.

Have fun in Kalymnos!

Do the ferries go late even in october?

My flight will arrive at around 21:30

I have never experienced difficulties getting tickets when showing up in time for the ferry. I have once seen the boat returning to Mastichari around midnight to pick up the last travellers that did not fit in on the first go. No warranty, but I think you can take this one easy…