ON TIMEBOARD

PDX → STS on time

Portland (Portland, OR) to Charles M. Schulz Sonoma (Santa Rosa, CA). Every scheduled flight, September 2025 to August 2026.

On time
83%
arrived < 15 min late
Cancelled
1.1%
848 flights
Typical arrival
−8 min
median vs schedule
When late
+59 min
average delay
Flights / day
2
1 airline

83% of flights from Portland to Santa Rosa arrived on time over the past 12 months. That is better than the typical U.S. route. The 2 p.m. departures ran on time 92% of the time; the 7 a.m. ones 75%. 7% of flights arrived more than an hour late or not at all.

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for PDX → STS: when a flight was late, it was under 45 minutes late 64% of the time. About 1 in 24 flights landed an hour or more late, and 1 in 212 three hours or more; 1.1% were cancelled outright.

Share of all 848 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
Alaska Airlines84883%1.1%−8 min4.2%+59 minSkyWest 74%, Horizon Air 23%, Alaska Airlines 3%

Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.

Best time of day to fly

On-time rate by scheduled departure hour (local time at PDX). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%7 a.m. departures: 75% on time (284 flights)757a8 a.m. departures: too few flights8a9 a.m. departures: too few flights9a10 a.m. departures: too few flights (80 flights)10a11 a.m. departures: too few flights11anoon departures: too few flights12p1 p.m. departures: too few flights1p2 p.m. departures: 92% on time (155 flights)922p3 p.m. departures: too few flights (83 flights)3p4 p.m. departures: too few flights4p5 p.m. departures: 84% on time (103 flights)845p6 p.m. departures: too few flights (21 flights)6p7 p.m. departures: too few flights (13 flights)7p8 p.m. departures: too few flights8p9 p.m. departures: 89% on time (108 flights)899p
PDX → STS, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

Last flight of the day

On PDX → STS, each airline's last flight of the day was cancelled 1.7% of the time, against 0.4% for its earlier flights (4.2× as often). It arrived 3+ hours late 0.0% of the time (earlier flights: 0.8%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
Alaska Airlines9:45 p.m.1.7%0.0%0.4%first flight 10:45 a.m.

Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.

If you need to be in STS tonight, book an earlier flight so there's a backup if it's cancelled.

By month

Each calendar month pooled over 2023–2026. Best: May (89%). Worst: January (74%).

40%70%100%Jan: 74% on time (122 flights)74JanFeb: 84% on time (109 flights)84FebMar: 84% on time (161 flights)84MarApr: 83% on time (189 flights)83AprMay: 89% on time (204 flights)89MayJun: 87% on time (205 flights)87JunJul: 89% on time (213 flights)89JulAug: 85% on time (211 flights)85AugSep: 88% on time (151 flights)88SepOct: 79% on time (151 flights)79OctNov: 78% on time (145 flights)78NovDec: 75% on time (153 flights)75Dec

By day of week

DayFlightsOn timeCancelled
Monday13081%0.8%
Tuesday11181%1.8%
Wednesday11790%0.9%
Thursday12786%0.0%
Friday12884%2.3%
Saturday10783%0.0%
Sunday12877%1.6%

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Airline (crew, maintenance, ops) 38%Severe weather 29%Late inbound plane 19%Air traffic & airport (NAS) 14%

Cancellations: weather 5 · airline 3 · air traffic/airport 1

Month by month

Not enough months with data to draw a trend.

Flight numbers on this route

Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.

FlightDepartsFlightsOn timeCancelledTypical arrivalOperated by
AS 34837:15 a.m.31077%0.7%−5 minSkyWest

Worst days in the past year

DateFlightsOn timeCancelled
Mar 22, 2026333%1
Aug 25, 2026333%0
Mar 31, 2026367%0
Aug 27, 2026367%0
Apr 18, 2026367%0

Questions

How often are flights from PDX to STS on time?

83% of 848 scheduled flights from Portland, OR to Santa Rosa, CA arrived within 15 minutes of schedule between September 2025 and August 2026. 1.1% were cancelled.

What is the best time of day to fly PDX to STS?

Flights scheduled to leave at 2 p.m. were the most reliable (92% on time). The 7 a.m. departures were the least (75%).

What month has the most delays from PDX to STS?

January (74% on time). The best month is May (89%), over 2023–2026.

Is the last flight of the day from PDX to STS more likely to be cancelled?

Yes. Each airline's last PDX–STS flight of the day was cancelled 1.7% of the time over the past year, against 0.4% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.