If airport security delays cause you to miss a flight in the United States, the airline may treat the situation as a missed departure depending on the circumstances and ticket rules. Security screening is operated by federal authorities, while flight reservations are controlled by airlines.
Missing a flight due to long security lines does not automatically guarantee rebooking without cost.
What happens
Passengers must pass through security screening before reaching the departure gate.
If security delays are longer than expected and you arrive at the gate after boarding has closed, you miss your flight in the United States even if you were already at the airport:
- The airline may mark the reservation as a no-show.
- Your seat may be released to standby passengers.
- Remaining segments of the itinerary may be canceled if they are part of the same ticket.
Airlines generally expect passengers to arrive at the airport early enough to complete security screening.
What determines the outcome
Several factors influence whether the airline will help rebook the passenger:
- The airline’s ticket rules.
- Whether the passenger checked in before the cut-off time.
- Availability of seats on later flights.
- Airline policies regarding missed departures.
In some cases, airline staff may offer same-day standby options if seats become available.
What it may lead to
Common outcome:
- Passenger requests standby on a later flight if passengers are placed on standby when seats open on later departures.
- Passenger rebooks with a change fee or fare difference.
Possible escalation:
- Remaining itinerary canceled due to no-show status.
- Same-day replacement ticket required.
Worst realistic outcome:
- Passenger must purchase a new ticket at last-minute prices if no seats are available on later flights after missing the original departure.
Airline responses vary widely depending on ticket conditions and seat availability.
Common escalation triggers
Situations that often lead to missed flights during security screening include:
- Long security lines during peak travel times.
- Additional screening procedures.
- Arriving at the airport close to departure time.
- Busy travel periods or staffing shortages.
These conditions can significantly increase security wait times.
What this depends on
Outcomes vary based on:
- Airline ticket rules.
- Airport security wait times.
- Passenger arrival time at the airport.
- Seat availability on later flights.
Airlines typically recommend arriving at the airport several hours before departure to account for possible delays.
Who controls the process
Airport security screening is conducted by the Transportation Security Administration (TSA), a federal agency.
Airlines control flight reservations, check-in deadlines, and rebooking decisions.
These systems operate separately even though both affect the travel process.
Last reviewed: March 2026
This page describes typical operational outcomes. Individual cases vary.