BTS on-time data, daily instead of two months later
The Bureau of Transportation Statistics publishes the official US airline on-time record, free, with decades of history. It arrives about two months after the month it describes and covers the airlines required to report. PlaneTrack publishes on-time performance for every major US airport and airline the next morning, from FAA departure data, with the individual departures behind each number. The two complement each other.
What BTS on-time data gives you
- The official record: the Airline On-Time Performance database and the Air Travel Consumer Report from the US Department of Transportation, free to download.
- Monthly figures for the reporting carriers (the larger US airlines, as defined by DOT revenue thresholds), with causes of delay (carrier, weather, national aviation system, security, late aircraft), cancellations and diversions.
- Arrival-based on-time (arrived within 15 minutes of schedule) as well as departure data, consistent since 1987, by airline, airport and flight number.
- Publication roughly two months after the end of the month, once carriers have reported.
It is the right source for official, long-run, cause-coded statistics and for anything that must match the DOT's own numbers.
What PlaneTrack gives you
- Next-morning US on-time data from FAA SWIM departure times: each day's departures are rolled up overnight and published the next morning, by airport, airline, route and flight number.
- Per-flight evidence. Every aggregate rests on individual departures with a scheduled time, an actual take-off time and a taxi-adjusted delay, delivered as CSV in the airport month-pack or looked up through the API.
- Open method. On time = took off within 15 minutes of schedule after subtracting the airport's normal taxi time; the method is printed on every page.
- Aircraft histories: every position we received for one aircraft over a date range, as a CSV, from $9.99 (free one-day sample).
- Live positions and tracks through the Flight Data API: a free tier, then $29 or $199 a month.
- One-off reports: airport month-pack $49, address overhead report $29, no account needed.
- Free samples: a fixed 7-day US on-time sample and the monthly State of the Sky report, both CC BY 4.0.
Side by side
| BTS on-time data | PlaneTrack | |
|---|---|---|
| Timeliness | About two months after the month | Next morning, every day; month pages update daily, then freeze |
| Airlines covered | Reporting carriers (larger US airlines); regional flights appear under the marketing or operating carrier per the DOT rules | Every scheduled airline in FAA SWIM data, regional partners under their own names |
| Measure | Arrival within 15 minutes (A14) and departure data, cause codes, cancellations | Departure within 15 minutes after the airport's normal taxi time; average delay; share 45+ minutes late. No cause codes or cancellations |
| History | Since 1987 | Since August 2026 |
| Granularity | Per flight, monthly files | Per flight (month-pack CSV, API) and per day on every month page |
| Cost | Free | Free month pages and 7-day sample; month-pack $49; API from $29; histories from $9.99 |
| Status | Official government statistics | Independent, derived from FAA SWIM; method printed on every page |
Use BTS on-time data when
- You need the official DOT numbers, cause-of-delay codes or cancellation counts.
- You are studying trends over years or decades.
- Your audience expects arrival-based on-time as the DOT reports it.
Use PlaneTrack when
- You need to know how an airport or airline did yesterday, last week or so far this month.
- You want regional airlines ranked under their own names, and smaller airlines the DOT does not require to report.
- You want the departures behind a number, as rows, the next morning.
- You are writing about a storm, an outage or a holiday weekend while it is still news.
Where PlaneTrack is the smaller source
Our on-time data covers scheduled airline departures in US airspace only (FAA SWIM), and the series starts in August 2026, so there is no multi-year history yet. Arrival delay is not part of the on-time measure; it is departure-based (wheels-off against schedule). Live and historical position coverage reflects where receivers see aircraft, so it is strongest in North America and Europe. If you need worldwide schedules, arrival-based statistics or a long back history, the sources on this page are the right tools.
Why the numbers differ
BTS on-time is arrival-based: a flight is on time if it arrives within 15 minutes of schedule. PlaneTrack measures the departure: wheels-off against the scheduled departure, after subtracting the airport's normal taxi time (FAA data reports take-off, not push-back). Flights that leave late and make up time in the air count as late here and on time at BTS; the reverse happens with flights that depart on time and arrive late. Airline sets also differ, so expect the two to agree on direction and rank more often than on the exact figure.
See a live example: on-time performance by airport and airline, month by month, or the monthly State of the Sky.
Facts about the other source are taken from its public documentation and can change; we do not quote its prices. Facts about PlaneTrack are what our own site says. Tell us at [email protected] if anything here is out of date.