Routes & Connections

Route Reliability Check

Enter two U.S. airport codes to see every airline that flies the route ranked by on-time arrival rate — with typical and worst-case delays and cancellation rates — from the U.S. DOT's on-time performance filings over the last 12 months.

FromToWindow

Try a route:ATL → LGA LAX → JFK ORD → DFW SFO → SEA

Busiest U.S. routes

The 300 highest-volume directed routes in the current filing, each scored over the trailing 12 months. Routes are directional — the return leg is filed separately and often performs differently.

Methodology

Every figure is computed directly from the U.S. Department of Transportation's Marketing Carrier On-Time Performance filing (Bureau of Transportation Statistics, table 236), reduced to monthly per-route, per-carrier aggregates. For the window you choose, the tool sums those monthly rows — on-time counts, cancellations, and the full arrival-delay distribution — for the exact origin → destination direction you enter.

On-time % = arrivals under 15 minutes late ÷ arrivals with a filed arrival time. The 15-minute threshold is the federal definition of on-time (14 CFR § 234.2), used unchanged.
Typical delay (median) and Worst 10%(90th percentile) are read from the summed arrival-delay distribution. Because the distribution is stored rather than a precomputed average, a multi-month median is exact — not an average of monthly medians, which would be wrong. Values are clamped to a −60…+240 minute domain and shown as a bound (“≥ +240 min”) when they land on the edge.
Cancelled % = cancelled flights ÷ all scheduled operations. Cancellations sit beside on-time rate deliberately: a cancelled flight is never counted late, so a carrier can lift its on-time number by cancelling — the two figures only make sense together.

Scope & limits. U.S. domestic operations of reporting marketing carriers, January 2018 onward; this tool serves Jul 2025 onward. Flights are attributed to the marketing carrier — the airline on the ticket — so a regional-operated codeshare counts toward the brand you booked. A carrier with fewer than 30 filed arrivals on the route is listed with its flight count but not rated. Historical performance only: no live tracking, and no predictions.

Last reviewed: July 2026

Frequently asked questions

Which airline does a delay count against — the one on my ticket or the regional that flew it?

The airline on your ticket. This tool uses the DOT's Marketing Carrier filing, so a flight sold as Delta but operated by a regional partner counts toward Delta — the carrier you actually chose when you booked. That is usually the airline the question is about.

Why can the same route show different numbers in each direction?

Because they are different operations. ATL → LGA and LGA → ATL are filed and scored separately, and morning and evening banks, connecting traffic, and airport congestion differ by direction. The tool shows the direction you enter and offers a one-click switch to the reverse.

What exactly does "on time" mean here?

The federal definition: a flight is on time if it arrives at the gate less than 15 minutes after its scheduled arrival. Arrive 14 minutes late and it counts as on time; 15 and it counts as delayed. Every figure on this site uses that rule unchanged (14 CFR § 234.2).

Why do some airlines on my route show no on-time rate?

A rate or a delay percentile built from a handful of flights is noise, not a statistic. When a carrier filed fewer than 30 arrivals on the route over the window, the tool shows the flight count and marks it too small to rate rather than publishing an unreliable number.

Related tools

Connection Risk Calculator

How often a given layover at a connecting airport actually works, from the historical arrival record of the inbound route.

Open tool →Airline On-Time Rankings

Every reporting U.S. airline ranked by on-time arrival rate over the last 12 months, with cancellation and diversion rates alongside — because a carrier can lift its on-time number by cancelling.

Open tool →Airline Head-to-Head

Compare any two U.S. airlines side by side — on-time arrival rate, cancellations, diversions, typical and worst-case delay, and delay causes — from the DOT's on-time performance filings.

Open tool →Airport Delay Profile

Departure and arrival reliability at a U.S. airport, month by month, with the DOT delay-cause split — carrier, weather, National Aviation System, security, and late-arriving aircraft.

Open tool →