To check in for a Delta flight, you can do so online, through the mobile app, at a self-service kiosk, or at the airport check-in counter. Online check-in opens 24 hours before departure and closes 30 minutes before domestic flights and 60 minutes before international flights. To check in online, go to the airline’s website or use the mobile app, enter your confirmation number or SkyMiles number and last name, then follow the steps to confirm your flight details, select or change your seat, and add any checked baggage if needed. Once check-in is complete, you can download or email your boarding pass or save it to your mobile wallet. If using the mobile app, the boarding pass will be available directly within the app for convenience at security and boarding. At the airport, you can use Delta’s self-service kiosks by entering your confirmation number, scanning your ID, or swiping a credit card used during booking. The kiosk allows you to check in, print boarding passes, and print bag tags if you have checked luggage. After tagging your bags, drop them at the baggage drop counter. If you prefer or need assistance, check-in agents are available at the full-service counter to help with check-in, special requests, or complex itineraries. Travelers with pets, special service needs, or international documentation requirements should check in at the counter. It is recommended that you arrive at the airport at least two hours before a domestic flight and three hours before an international flight to allow enough time for check-in, baggage drop, security screening, and reaching the departure gate. Check-in deadlines vary by airport and destination, so ensure you meet the cutoff times to avoid delays or denied boarding. Once checked in and with your boarding pass in hand, proceed to security and your gate. If you are traveling without checked bags, online or mobile check-in allows you to skip the check-in counter and go directly to security. The airline also allows group check-in for passengers on the same booking, and the process is similar for both domestic and international travel, though international flights may require additional document verification. Boarding begins around 30 to 40 minutes before departure, so be at the gate early with identification and boarding pass ready. Efficient check-in ensures a smoother airport experience and reduces the risk of missing your flight.