For a 2026 trip to Croatia, buying ferry tickets in advance is highly recommended during the peak season (June to September), but optional during the winter. Popular routes like Split to Hvar or Dubrovnik to Korčula are served by high-speed catamarans that have limited seating and frequently sell out days in advance. If you are traveling with a car, advance booking for large ferries (like Jadrolinija) is an absolute must, as vehicle space is extremely competitive. In 2026, many operators offer high-value e-tickets via apps like Ferryhopper or MrFerry, allowing you to bypass long ticket office queues at the port. While you can technically buy "deck passage" for large ferries on the day, doing so for catamarans is risky. For a premier island-hopping experience, booking 2–4 weeks ahead ensures you get your preferred departure time and avoids the stress of being stranded at the pier in the Mediterranean heat.