Two hours before a domestic flight, three before an international one, and add 30–45 minutes at mega-hubs, on holiday weekends, or if you're checking bags. PreCheck/Fast Track lets you trim about 30 minutes.
The standard advice — two hours domestic, three international — exists because the slow parts are variable: bag drop lines, security, and the walk to the gate. At small airports you can cut it; at JFK, LAX, LHR, CDG or FRA you should not.
Add time when:
- You’re checking bags (bag-drop cutoffs are usually 45–60 minutes before departure).
- It’s a holiday period, a Monday morning or a Friday evening.
- You’re flying to the US from an airport with pre-clearance (Dublin, Abu Dhabi, Toronto): add 45–60 minutes.
- Your airline uses a far-flung terminal or a bus gate.
Cut time when: you have PreCheck, Fast Track or a lounge-access fast lane, no bags, and a mobile boarding pass — 75–90 minutes domestic is realistic at a mid-size airport.
Boarding usually closes 15–20 minutes before departure (up to 45 on some international flights). Work backwards from that, not from the departure time.
Related questions
What time does boarding close before a flight?
Most airlines close the gate 15–20 minutes before departure for domestic flights and 30–45 minutes for international. The time on your boarding pass is the boarding start, not the deadline. Full answer →
Is TSA PreCheck worth it?
If you fly two or more times a year from US airports, yes: shorter lines, shoes and laptops stay put, and many credit cards reimburse the fee. Global Entry costs slightly more and includes PreCheck plus faster US immigration — the better buy for international flyers. Full answer →
How long does airport security take?
Usually 10–30 minutes, but 45–60+ at large hubs during morning and holiday peaks. Many airports publish live wait times; PreCheck, Fast Track and off-peak departures are the reliable ways to shorten it. Full answer →
Airline, airport and government rules change without notice. Treat this as a starting point and confirm with the airline or authority for your specific trip. Request a correction if something is out of date.