How Far in Advance Can You Book a Flight is a common question among travelers planning trips. Most airlines, including American Airlines and Delta Air Lines, allow passengers to book flights up to 11 months in advance, depending on their schedule release. Booking early can help secure better fares and preferred seats, especially during peak travel seasons. However, prices may fluctuate over time, so timing matters. Travelers are advised to compare fares, set alerts, and plan ahead to find the best deals while ensuring flexibility for any schedule changes.