If you're flying with KLM Royal Dutch Airlines, it’s important to know exactly how long before your flight you can check in to ensure a smooth start to your journey. KLM offers passengers multiple check-in options including online check-in, mobile app check-in, self-service kiosks, and airport check-in counters. For most flights, KLM online check-in opens 30 hours before the scheduled departure time and remains available until 1 hour before departure for most destinations. However, for flights departing from or to the United States, online check-in opens 24 hours before departure due to U.S. travel regulations. You can check in through the official KLM website or the KLM mobile app using your booking code and last name. Online check-in allows you to select or change your seat, add extra baggage, input travel documents for international flights, and download or email your boarding pass. For passengers traveling with only cabin baggage, online check-in provides the convenience of skipping lines and heading straight to the gate after security. If you are traveling with checked luggage, you can still use online check-in and simply drop off your bags at the KLM baggage drop-off counter, which typically closes 40 to 60 minutes before departure, depending on the airport. At the airport, KLM check-in counters usually open 3 hours before international flights and 2 hours before short-haul or European flights. It’s recommended to arrive at the airport at least 3 hours before international flights and 2 hours before intra-Europe flights to allow enough time for check-in, baggage drop, security screening, and passport control. KLM also provides self-service kiosks at many international airports where you can print your boarding pass and baggage tags quickly. These kiosks are especially useful during peak travel times or when airport staff lines are long. For travelers flying in Business Class or those with Flying Blue Elite status, KLM offers priority check-in counters that help expedite the process. Some passengers—such as those traveling with infants, pets, unaccompanied minors, or requiring special assistance—may be asked to check in at the airport counters regardless of whether online check-in was completed. It’s essential to confirm the exact check-in and baggage drop-off deadlines for your specific airport and route, as they can differ slightly based on destination and regulations. KLM also sends timely notifications and reminders via email or the mobile app when it’s time to check in, keeping passengers informed throughout the process. In summary, you can check in online for your KLM flight 30 hours before departure (or 24 hours for U.S.-bound flights), and airport check-in opens about 3 hours prior for long-haul routes. To avoid delays or missed flights, it’s best to complete online check-in as soon as it becomes available and arrive early at the airport, especially if you have bags to check or are flying internationally. Following these steps ensures a seamless check-in process with KLM and a comfortable start to your travel experience.