FlightRecord

Charles M. Schulz Sonoma County Airport (STS): Delays & On-Time Performance

Data through May 2026

Charles M. Schulz Sonoma County Airport (STS) is a tale of two seasons: departures ran 88% on-time in March 2026 but sank to 65% in December 2025. Across the year it averages 80% against a national 78%, over roughly 14 departures a day to 12 destinations.

Departures on-time
80%
left <15 min late
Avg dep delay
15 min
Arrivals on-time
79%
Cancelled
1.3%
Destinations
12
nonstop
Airlines
5

Monthly on-time trend

Monthly departure on-time percentage at STS50%75%100%June 2024: 76% on-time (287 flights)76Jun 2024July 2024: 83% on-time (319 flights)83August 2024: 83% on-time (338 flights)83September 2024: 83% on-time (345 flights)83Sep 2024October 2024: 81% on-time (348 flights)81November 2024: 74% on-time (396 flights)74December 2024: 76% on-time (387 flights)76Dec 2024January 2025: 84% on-time (279 flights)84February 2025: 79% on-time (250 flights)79March 2025: 82% on-time (319 flights)82Mar 2025April 2025: 80% on-time (363 flights)80May 2025: 79% on-time (455 flights)79June 2025: 73% on-time (404 flights)73Jun 2025July 2025: 72% on-time (385 flights)72August 2025: 80% on-time (435 flights)80September 2025: 82% on-time (484 flights)82Sep 2025October 2025: 85% on-time (404 flights)85November 2025: 81% on-time (484 flights)81December 2025: 65% on-time (406 flights)65Dec 2025January 2026: 85% on-time (364 flights)85February 2026: 87% on-time (323 flights)87March 2026: 88% on-time (443 flights)88Mar 2026April 2026: 86% on-time (558 flights)86May 2026: 84% on-time (589 flights)84

Best time of day to depart from STS

On-time percentage by scheduled departure hour at STS6 a.m.: 94% on-time (609 flights)67 a.m.: 91% on-time (955 flights)78 a.m.: 90% on-time (151 flights)89 a.m.: 77% on-time (318 flights)910 a.m.: 80% on-time (743 flights)1011 a.m.: 82% on-time (609 flights)1112 p.m.: 76% on-time (990 flights)121 p.m.: 80% on-time (404 flights)132 p.m.: 76% on-time (1,028 flights)143 p.m.: 78% on-time (608 flights)154 p.m.: 81% on-time (962 flights)165 p.m.: 80% on-time (240 flights)176 p.m.: 79% on-time (744 flights)187 p.m.: 76% on-time (750 flights)198 p.m.: 65% on-time (234 flights)20scheduled departure hour

Busiest routes from STS

RouteFlights/12moOn-timeAvg delay
STS → SAN90273%17 min
STS → SNA74677%17 min
STS → PHX69380%16 min
STS → LAX68881%13 min
STS → PDX55886%11 min
STS → BUR53176%14 min
STS → SEA48170%17 min
STS → LAS28779%18 min

Most reliable routes

  1. STS → PDX86%
  2. STS → PSP82%
  3. STS → LAX81%
  4. STS → PHX80%
  5. STS → LAS79%

Most delay-prone routes

  1. STS → DFW67%
  2. STS → SEA70%
  3. STS → SAN73%
  4. STS → BUR76%
  5. STS → SNA77%

Airline performance at STS

AirlineOn-time departuresAvg delayFlights
Envoy Air84%10 min788
SkyWest Airlines81%14 min7,276
Southwest Airlines79%13 min187
Alaska Airlines76%14 min658
American Airlines67%40 min456

Frequently asked questions

How often are flights delayed at STS?
20% of departures from Charles M. Schulz Sonoma County Airport left 15+ minutes late between 2024-06 and 2026-05, with an average departure delay of 15 minutes. The national on-time average over the same period was 78%.
What is the best time of day to depart from STS?
Flights scheduled around 6 a.m. depart on time 94% of the time at STS, versus 65% around 8 p.m.. Booking before noon is the usual rule of thumb here.
What is the worst month for delays at STS?
In this dataset, December 2025 was the weakest month at STS, with 65% of departures on time.
How often are flights cancelled at STS?
1.3% of scheduled departures from STS were cancelled in this period, compared with a national rate of 1.6%.

Popular route pages from this airport

Based on 9,365 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.