Charles M. Schulz - Sonoma County in May 2025

79.3%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 May 2025, reporting carriers scheduled 455 domestic departures from Charles M. Schulz - Sonoma County (STS). 79.3% left less than 15 minutes late and 75.2% reached their destination on time; 0.0% were cancelled.

Nationally that month, 76.7% of flights departed on time and 75.4% arrived on time, so STS departures were 2.6 points above the national departure figure.

A year earlier, in May 2024, the airport had 242 departures with 83.1% leaving on time: a change of −3.8 points, with flights up 88%.

Flights arriving at STS that month were on time 80.0% of the time (455 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, late-arriving aircraft 49%, national aviation system 26% and air carrier 16%.

On time 75.2%
Arrived 15+ minutes late 24.4%
Cancelled 0.0%
Diverted 0.4%

Every scheduled departure from STS in May 2025, judged by arrival at the destination.

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

Measure	May 2025	May 2024	STS, 12 months to Jul 2026	All reported flights, May 2025
Departed on time	79.3%	83.1%	80.4%	76.7%
Arrived on time	75.2%	74.4%	78.8%	75.4%
Cancelled	0.0%	0.4%	1.7%	1.0%
Average departure delay (late minutes only)	12.5 min	18.4 min	13.2 min	17.5 min
Scheduled departures a day	15	8	16	20,188
Scheduled departures	455	242	5,714	605,648

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
OO SkyWest Airlines	341	75%	77.4%	7.1 min	0.0%
AA American Airlines	58	13%	75.9%	10.2 min	0.0%
MQ Envoy Air	31	7%	87.1%	10.1 min	0.0%
AS Alaska Airlines	25	5%	28.0%	38.0 min	0.0%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
STS–LAX	Santa Rosa to Los Angeles	62	82.3%	0.3 min	0.0%
STS–PDX	Santa Rosa to Portland	62	82.3%	10.4 min	0.0%
STS–PHX	Santa Rosa to Phoenix	62	87.1%	7.7 min	0.0%
STS–SAN	Santa Rosa to San Diego	62	66.1%	10.5 min	0.0%
STS–SNA	Santa Rosa to Santa Ana	62	75.8%	7.8 min	0.0%
STS–SEA	Santa Rosa to Seattle	56	55.4%	21.6 min	0.0%
STS–BUR	Santa Rosa to Burbank	31	77.4%	3.3 min	0.0%
STS–LAS	Santa Rosa to Las Vegas	31	83.9%	8.4 min	0.0%
STS–DFW	Santa Rosa to Dallas/Fort Worth	27	63.0%	16.0 min	0.0%

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), May 2025.

Delay causes

BTS cause category	Share of delay minutes	National, May 2025	Minutes
Air carrier	16.3%	29.3%	969
Late-arriving aircraft	48.7%	37.8%	2,904
National Aviation System	26.0%	25.9%	1,553
Extreme weather	9.0%	6.9%	537
Security	0.0%	0.1%	0

5,963 delay minutes on 111 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 STS on time in May 2025?

79.3% of 455 scheduled domestic departures left less than 15 minutes late, and 75.2% reached their destination on time. The national figures that month were 76.7% and 75.4%.

How does that compare with a year earlier?

In May 2024, 83.1% of 242 departures left on time and 0.4% were cancelled, against 79.3% and 0.0% in May 2025.

Provenance

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