How Often Do Flights Get Delayed? The U.S. Data Explained

How often do flights get delayed in the United States?

The clearest recent full-year answer is roughly a quarter of reported domestic flights. The U.S. Department of Transportation's Bureau of Transportation Statistics (BTS) recorded 1,685,316 arrival delays across 6,901,794 flight operations in 2025. Its published delayed rate was 24.42%.

That is a useful planning baseline, not a promise about any particular departure. The national result combines different airlines, airports, routes, seasons and operating conditions. BTS data also covers reporting carriers and qualifying domestic operations rather than every flight in every part of aviation.

The headline can answer “how often,” but the month-by-month figures explain why two travelers can have very different experiences. In 2025, the reported delayed rate reached 27.72% in July and fell to 16.15% in September. Your flight's risk is shaped by the conditions affecting its aircraft and route on the day.

What counts as a delayed flight?

Delay statistics are easy to misread because BTS and the Federal Aviation Administration (FAA) measure related but different parts of the system. BTS publishes airline on-time performance for consumer comparison. FAA systems also track delays created by air-traffic constraints. Those datasets are not interchangeable.

Official measure	What it describes	Best use
BTS airline on-time performance	Reported domestic flight operations, including on-time arrivals, arrival delays, cancellations and diversions	Estimating how often a passenger flight arrives late
BTS cause reporting	Delay causes assigned to air carrier, NAS, weather, late-arriving aircraft or security categories	Understanding why reported airline delays occurred
FAA OPSNET	Instrument-flight-rule traffic delayed by the air-traffic system for 15 minutes or more	Understanding system constraints such as weather, traffic volume, equipment or runway capacity

This distinction matters. An FAA statistic about system-impacting delay is not automatically the percentage of airline passengers whose flights arrived late. Likewise, the BTS airline rate does not say that air traffic control caused every late arrival.

How much did the delay rate vary by month?

BTS's 2025 monthly table shows that delay frequency moved substantially through the year. The selected months below are from the same national dataset and use the same published arrival-delay measure.

Month in 2025	Arrival delays	Published delayed rate
January	109,606	18.31%
June	186,766	27.70%
July	192,888	27.72%
September	100,368	16.15%
December	170,133	26.38%

The table does not prove that the calendar alone caused these changes. It shows why a single annual average cannot forecast a specific trip. Conditions can affect the departure airport, arrival airport, the airspace between them or the aircraft's earlier legs.

Why do flights get delayed?

BTS uses five broad cause categories: air carrier, National Aviation System (NAS), extreme weather, late-arriving aircraft and security. Each category answers a different operational question.

Air-carrier causes

An air-carrier delay is within the airline's control. BTS examples include maintenance or crew problems, aircraft cleaning, baggage loading and fueling. The Department of Transportation uses the same basic idea when describing a controllable delay on its Airline Cancellation and Delay Dashboard.

National Aviation System causes

NAS delays cover a broad set of conditions in the national aviation system, including non-extreme weather, airport operations, heavy traffic volume and air traffic control. This is one reason a simple “weather” label can understate weather's wider effect: BTS explains that some weather that slows the system is recorded inside the NAS category rather than as extreme weather.

Extreme weather

BTS reserves its extreme-weather category for significant actual or forecast conditions that, in the airline's judgment, delay or prevent a flight. The FAA separately says weather is the largest cause of system-impacting air-traffic delay. Its analysis found weather behind 74.26% of those delays longer than 15 minutes over the six years from June 2017 through May 2023.

That 74.26% is not the share of all passenger flights delayed by weather. It describes a defined set of FAA system-impacting delays and includes more than scheduled airline service. Use it to understand the air-traffic system, not as a personal probability.

Late-arriving aircraft

A late-arriving-aircraft delay occurs when the same plane reaches its previous airport late, pushing back the next trip. The FAA calls the downstream ripple “delay propagation.” This explains why clear weather outside your terminal does not guarantee an on-time departure: the aircraft may already be behind schedule somewhere else.

Security causes

BTS and FAA descriptions include terminal or concourse evacuation, reboarding after a security breach, screening-equipment problems and screening lines longer than 29 minutes. This is a defined reporting category, not a general label for every slow checkpoint.

Does a delayed flight usually get cancelled?

No. BTS reports delay and cancellation as separate outcomes. In the 2025 table, it recorded 1,685,316 arrival delays and 106,633 cancellations across 6,901,794 operations. A late flight may still operate, while a cancellation means the scheduled operation did not depart.

A delay can grow in stages. DOT calls this a “creeping delay”: the expected departure keeps moving because new information changes the estimate. Weather may fail to improve as forecast, or a mechanical problem may take longer to resolve. That is why an initial short delay does not establish the final departure time.

For a closer look at the separate cancellation question, read how often flights get cancelled. If a disruption is already showing on your booking, use why is my flight delayed to decode the operational reason.

How to judge the risk for your own flight

No national percentage can predict one flight. A better pre-departure check combines airport-wide conditions with the status of the actual aircraft and itinerary.

1. Check the airline first. The FAA says the airline provides up-to-date information for a specific flight. Confirm the operating carrier as well as the brand that sold the ticket.
2. Check both airports. FAA NASstatus shows airport status and system delay information. Conditions at the arrival airport can hold a departure at its gate even when the departure airport looks calm.
3. Look for an inbound-aircraft problem. If the same aircraft arrived late on its previous trip, BTS classifies the resulting ripple as a late-arriving-aircraft delay.
4. Treat estimates as estimates. DOT warns that creeping delays can lengthen when weather or a mechanical issue develops differently than expected.
5. Keep your onward plan usable offline. Save the boarding pass, terminal map and connection details before leaving reliable service. If a late arrival threatens a connection, see what happens after a delay makes you miss a connection.

What should you expect from the airline?

For disruptions within an airline's control, the DOT dashboard compares voluntary customer-service commitments such as rebooking, meals, hotels and ground transportation. A green check means the airline has committed to that service; a red mark means it has not made that commitment, although it may still help at its discretion.

Do not assume every delay produces the same assistance. DOT says each airline has its own policies, and the dashboard focuses on controllable events. Ask the airline to identify the cause, explain the next confirmed option and state which written commitment applies.

DOT also says airline commitments do not replace refund rights when the carrier cancels or makes a significant change and the passenger declines the alternative offered. For the refund decision, see how to request a plane-ticket refund.

The practical answer

So, how often do flights get delayed? The most useful recent U.S. baseline is 24.42% of reported domestic operations in 2025, but the monthly result moved substantially between September and July. Use the annual figure to set expectations and live airline and FAA information to make decisions on travel day.

Definitions, reporting coverage and airline commitments can change. Confirm current flight status and applicable policy with the airline and the official agency source before flying.