Which Washington airport should you fly from?

IAD is clearly ahead on on-time arrival. On the other two rates the airports cannot be told apart, so this is the only difference the data supports.

IAD is clearly ahead of the rest on 2 of 4 rates; the other 2 are too close to call: BWI and IAD on 1, DCA and IAD on 1.

A check mark and green mark the best figure in a row (higher for on-time rates, lower for delays and cancellations) when it is clearly better than every other airport’s: a two-proportion test on each airport’s flight count, at about 95% confidence. Otherwise the row says “too close to call” and a “≈” marks the airports that cannot be told apart from the best figure. Average and median delay carry no sample-error estimate here, so they are marked by the printed figure alone.

• On-time arrival. IAD is clearly higher: IAD 83.6%, DCA 79.8%, BWI 74.7% (8.9 points from best to worst).
• Cancellation rate. Too close to call between BWI and IAD: BWI 1.08%, IAD 1.19%, DCA 2.83%.
• Severe delay (60+ min). Too close to call between DCA and IAD: IAD 6.4%, DCA 7.2%, BWI 7.9%.

The airlines differ: DCA is 45% Republic Airways, BWI is 100% Southwest Airlines, and IAD is 82% Republic Airways. A gap between airports can be a gap between airlines.

The same airline from different airports

• Republic Airways flies it from DCA and IAD: DCA 85.1% (2,837 flights), IAD 83.3% (2,417 flights); the on-time gap is within what chance could produce.
• Southwest Airlines flies it from DCA and BWI: DCA 80.5% (1,113 flights), BWI 74.7% (3,425 flights); DCA is clearly better on time.

Airline figures need 200 flights on the route and use the same test. The airline is the same, so a gap is not about who flies; the flights each carries still differ.

By departure time

A window needs 120 flights on the route to be scored. 1 of the 6 windows with two or more scored airports has a clear leader; a route is a small sample next to a whole airport, so the rest cannot be called.

How the best airport is chosen. An airport is called best only when it is clearly ahead on at least two of on-time arrival, cancellation rate and severe delay, and no other airport is clearly ahead on any of them. A lead the flight counts cannot separate from chance is reported as too close to call, which a route with a few thousand flights produces often.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – August 2026 · Each route is measured over its own period. Departures from DCA, BWI, and IAD only.

• On-time arrivalIAD had the best on-time arrival rate, 80.8%, ahead of DCA at 76.3%, BWI at 75.8%. Best to worst is 5.0 points.
• CancellationsDCA cancelled 3.06% of its flights, 2.3 times the rate at IAD (1.31%).
• Taxi timeTaxi-out averages 21.7 min at DCA and 15.3 min at BWI, 6.4 minutes more between pushback and wheels-up. Coming in, taxi time runs from 6.0 min at BWI to 7.7 min at DCA.
• Time of dayThe best airport depends on when you leave: clearly ahead IAD at 9 AM–12 PM, 12–3 PM, 3–6 PM, 6–9 PM, and 9 PM–5 AM and BWI at 5–9 AM. The gap is widest for departures at 9 PM–5 AM (IAD 78.3% against BWI 58.9%) and narrowest at 5–9 AM (1.3 points).
• Hour by hourThe biggest swing through the day is at BWI: 5 AM–6 AM reached 92.3% on time (2,563 flights) and 10 PM–11 PM fell to 54.0% (10,352), 38.3 points apart.
• AirlinesSouthwest Airlines flies 75% of departures from BWI, and one carrier also flies more than half at IAD. The largest carrier at each: Southwest Airlines at BWI (75%), United Airlines at IAD (62%), and PSA Airlines at DCA (28%). Carriers with 500 or more departures at only one of them: Spirit Airlines at BWI and Allegiant Air at IAD.
• Destinations105 destinations outside the metro area get 750 or more flights from these airports; 63 of them from at least two and 36 from every airport. DCA alone serves 36 destinations (16% of its departures), including Huntsville (HSV), White Plains (HPN), and Philadelphia (PHL).
• Same destinationsOn the 36 destinations every airport serves, on-time arrival runs from 76.0% at BWI to 81.1% at IAD: 5.1 points, about the same as the 5.0 points over all their flights; IAD leads clearly.

IAD is clearly ahead of the rest on 4 of 4 rates.

A check mark and green mark the best figure in a row (higher for on-time rates, lower for delays and cancellations) when it is clearly better than every other airport’s: a two-proportion test on each airport’s flight count, at about 95% confidence. Otherwise the row says “too close to call” and a “≈” marks the airports that cannot be told apart from the best figure. Average and median delay carry no sample-error estimate here, so they are marked by the printed figure alone.

Share of the metro is each airport’s part of the 929,523 departures at these 3 airports. Taxi-out is pushback to wheels-up on departure and taxi-in is touchdown to gate on arrival, averaged over all flights. The score is the FlyerIntel Reliability Score, 0 to 100.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – August 2026 · Departing flights only.

A window needs at least 120 flights at an airport to be scored. The check mark uses the same test as the table above. Gap is best minus worst among the scored airports.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – August 2026 · Windows are the scheduled local departure time at each airport.

Each chart has its own scale, so read the numbers in the table, not the bar heights, when comparing airports. The best and worst of 24 hours are the two extremes, so a small airport’s best hour is partly luck; the flight count is beside each. A swing under 3 points, or one the two hours’ flight counts cannot separate from chance, is marked as within noise.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – August 2026 · Hours are the scheduled local departure hour. An hour needs at least 120 flights to be scored.

Airlines are the operating carrier, so a regional airline flying for a larger one is listed under its own name. Only airlines with at least 500 departures at an airport are listed there.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – August 2026

Destinations every airport serves

36 places get 750 or more flights from each of DCA, BWI, and IAD. Counting only flights to those places (59% of DCA’s, 70% of BWI’s, and 83% of IAD’s departures):

The shared places: Atlanta (ATL), Austin (AUS), Hartford (BDL), Nashville (BNA), Boston (BOS), Charleston (CHS), Cleveland (CLE), Charlotte (CLT), Columbus (CMH), Cincinnati / Covington (CVG), Denver (DEN), Dallas–Fort Worth (DFW), Detroit (DTW), Fort Lauderdale (FLL), and 22 more.

The same airline at different airports

Where one airline flies from several of these airports, its own on-time rate at each. The airline is the same, so a gap is not about who flies, though the routes each flies from an airport still differ.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – August 2026 · Same test as above. A dash means the airline has fewer than 500 departures at that airport.

• Different airlines. PSA Airlines flies 28% of DCA’s departures; Southwest Airlines flies 75% of BWI’s departures; United Airlines flies 62% of IAD’s departures. An airline brings its own schedule, aircraft and habits to an airport, so part of every gap above is a gap between carriers.
• Different destinations. 16% of DCA’s departures, 2% of BWI’s departures, and 2% of IAD’s departures go to places no other airport here serves. An on-time arrival is counted at the far end, so weather and congestion at the destination are in the figure.
• Different trip lengths. The average route, weighted by flights, is 660 miles from DCA, 809 miles from BWI, and 1,047 miles from IAD. Short regional hops and long coast-to-coast flights fail in different ways.
• Ground time belongs to the airport. Taxi-out and the share of flights that push back on time measure the airport itself. On-time arrival measures the whole trip.
• History, not a forecast. These are flights from July 2023 – August 2026. A storm cancels hundreds of flights together, so a clear gap is a statement about this sample, not a promise about your trip.

• Chicago (ORD, MDW)
• New York (LGA, EWR, JFK)
• Dallas–Fort Worth (DFW, DAL)
• Los Angeles (LAX, SNA, BUR, ONT)
• San Francisco (SFO, SJC, OAK)
• Miami (MIA, FLL)
• Houston (IAH, HOU)