How far in advance should I book the Kos to Kalymnos ferry?

For July and August, book this route 3–6 weeks in advance. For May, June, September and October, 1–2 weeks is usually sufficient. Cabin berths on overnight ferries fill fastest — book as early as possible if you need a specific cabin class. Check the Teleporio Score before booking to identify the best departure window.

What happens if the Kos to Kalymnos ferry is cancelled due to bad weather?

When a Greek ferry is cancelled due to weather, operators are required to offer a full refund or rebooking on the next available sailing. You are not entitled to compensation for consequential costs such as hotels or flights missed as a result. Always build a buffer day before any onward flight or transport connection when island-hopping in summer, particularly on routes exposed to the Meltemi wind.

What is the Beaufort scale and how does it affect the Kos to Kalymnos crossing?

The Beaufort scale measures wind force from 0 (dead calm) to 12 (hurricane force). For Greek ferry travel, Beaufort 1–3 is ideal. Beaufort 4–5 means noticeable swell and possible motion sickness on smaller vessels. Beaufort 6–7 causes delays and cancellations on catamarans and hydrofoils. Beaufort 8 and above grounds most island ferry services completely. Teleporio’s Beaufort score factors current and forecast conditions into every route recommendation.

Teleporio™ — Greek Island Travel Intelligence

Kos to Kalymnos Ferry Guide

Kos to Kalymnos ferry guide. Fast catamaran takes 30 minutes. Operator schedules, Beaufort conditions, seasonal tips and George's advice.

Reviewed by Georgios — Teleporio™ route intelligence guide — Updated 2026-07-24

Analyzing real-time weather risks, vessel tracking thresholds, and luxury multi-modal transfer alternatives to ensure seamless island transit planning.

The Kos to Kalymnos Crossing

Dodekanisos Seaways operates the main catamaran service on this route — high-speed passenger vessels covering the 25 nautical miles between Kos Town and Pothia harbour in Kalymnos; the Mastichari–Kalymnos car ferry runs slower conventional services for vehicle transport

The crossing takes 25–30 minutes on the Dodekanisos Seaways catamaran; 35–45 minutes on the car ferry via Mastichari. 4–6 catamaran departures daily in summer (June–September); 2–3 car ferry departures daily; reduced frequency in winter

Sea Conditions and Beaufort Exposure

the Kos–Kalymnos channel is partially sheltered by the island mass of Kos, making it less exposed than open Cycladic crossings; Beaufort 4–5 is manageable on the catamaran; Beaufort 7+ may cause delays or cancellations; morning crossings before 09:00 are almost always calmer in summer

Booking and Tickets

tickets available at the Kos Town port kiosks on morning of travel in most conditions; advance booking recommended in July–August especially for the catamaran which carries limited passengers; Dodekanisos Seaways website and Greek ferry aggregators offer online booking

Arrival

Pothia harbour on Kalymnos is a characterful working port town with sponge shops, fish tavernas, and the distinctive blue-and-white decorated houses that make Kalymnos recognisable; the old sponge-diving quarter is a short walk from the ferry berth; for rock climbers, the main crags at Grande Grotta and Arginonta are accessible by taxi or local bus from Pothia