Seattle/Tacoma International in June 2025

71.7%departed on time

BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report.

In June 2025, reporting carriers scheduled 15,695 domestic departures from Seattle/Tacoma International (SEA). 71.7% left less than 15 minutes late and 70.2% reached their destination on time; 0.6% were cancelled.

Nationally that month, 71.4% of flights departed on time and 70.3% arrived on time, so SEA departures were level with the national departure figure.

A year earlier, in June 2024, the airport had 15,183 departures with 72.8% leaving on time: a change of −1.1 points, with flights up 3%.

Flights arriving at SEA that month were on time 71.5% of the time (15,693 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 38%, air carrier 37% and national aviation system 22%.

On time 70.2%
Arrived 15+ minutes late 28.9%
Cancelled 0.6%
Diverted 0.3%

Every scheduled departure from SEA in June 2025, judged by arrival at the destination.

June 2025 against a year earlier, the airport's year and the nation

Measure	Jun 2025	Jun 2024	SEA, 12 months to Jul 2026	All reported flights, Jun 2025
Departed on time	71.7%	72.8%	78.2%	71.4%
Arrived on time	70.2%	74.2%	78.6%	70.3%
Cancelled	0.6%	0.5%	0.9%	1.6%
Average departure delay (late minutes only)	16.0 min	15.5 min	13.2 min	22.1 min
Scheduled departures a day	523	506	452	20,386
Scheduled departures	15,695	15,183	164,821	611,575

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
AS Alaska Airlines	7,154	46%	62.7%	14.4 min	0.6%
DL Delta Air Lines	2,851	18%	81.3%	2.0 min	0.7%
OO SkyWest Airlines	2,722	17%	80.4%	3.6 min	0.1%
UA United Airlines	918	6%	76.8%	7.3 min	0.8%
WN Southwest Airlines	915	6%	65.6%	16.0 min	0.1%
AA American Airlines	621	4%	65.9%	11.9 min	2.9%
HA Hawaiian Airlines	188	1%	56.9%	28.7 min	0.0%
F9 Frontier Airlines	158	1%	65.2%	22.5 min	1.9%
B6 JetBlue Airways	79	1%	55.7%	20.5 min	2.5%
MQ Envoy Air	48	0%	66.7%	7.2 min	0.0%
NK Spirit Airlines	41	0%	68.3%	6.0 min	2.4%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
SEA–ANC	Seattle to Anchorage	701	66.2%	11.9 min	0.6%
SEA–DEN	Seattle to Denver	643	63.8%	20.5 min	0.8%
SEA–LAX	Seattle to Los Angeles	633	79.8%	3.7 min	0.6%
SEA–SFO	Seattle to San Francisco	630	71.4%	8.2 min	0.6%
SEA–PHX	Seattle to Phoenix	618	75.9%	6.4 min	0.2%
SEA–ORD	Seattle to Chicago	571	70.1%	8.3 min	0.7%
SEA–LAS	Seattle to Las Vegas	529	67.1%	9.5 min	1.3%
SEA–DFW	Seattle to Dallas/Fort Worth	495	59.2%	18.8 min	2.6%
SEA–GEG	Seattle to Spokane	471	71.1%	8.6 min	0.0%
SEA–SMF	Seattle to Sacramento	430	73.3%	10.1 min	0.0%
SEA–SAN	Seattle to San Diego	427	76.8%	3.9 min	0.7%
SEA–SJC	Seattle to San Jose	412	75.2%	6.7 min	1.5%

By scheduled departure hour

On-time share:under 62%6270768288% and over

Share of departures that left less than 15 minutes late, by scheduled hour (local time), June 2025.

Delay causes

BTS cause category	Share of delay minutes	National, Jun 2025	Minutes
Air carrier	37.1%	31.6%	86,525
Late-arriving aircraft	38.0%	40.6%	88,843
National Aviation System	22.1%	20.9%	51,591
Extreme weather	1.6%	6.9%	3,775
Security	1.2%	0.2%	2,797

233,531 delay minutes on 4,529 flights that arrived 15 or more minutes late and carried a cause report. Carriers assign the categories; see what each category means.

Questions and answers

How many flights left SEA on time in June 2025?

71.7% of 15,695 scheduled domestic departures left less than 15 minutes late, and 70.2% reached their destination on time. The national figures that month were 71.4% and 70.3%.

How does that compare with a year earlier?

In June 2024, 72.8% of 15,183 departures left on time and 0.5% were cancelled, against 71.7% and 0.6% in June 2025.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for June 2025; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for SEA · methodology · corrections.