Flight number record

OO 3881

SkyWest Airlines · Seattle to Sacramento

Route: SEA → SMF
Departs: 08:20
Flights: 357
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 3881, check with SkyWest Airlines. SkyWest Airlines flies under contract for larger airlines, so a ticket for this flight may show a different airline code and number.

OO 3881 earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 15 points better than the national rate of 77.6%. When something does go wrong the average delay runs an hour and a half. That rests on 357 flights, with a median arrival 11 minutes early.

Set against the rest of the country, OO 3881's record is 15 points better than the US average of 77.6%. That gap is worth roughly 148 fewer late arrivals for every thousand flights.

On time

92.4%

Arrivals under 15 minutes late, of 355 completed flights

Avg delay

84 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

3.4%

National rate is 8.1%

These figures cover 357 flights between July 2025 and June 2026. The median arrival is 11 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

Schedule

When OO 3881 flies

OO 3881 flies SEA to SMF without a single fixed slot. Its most common scheduled departure was 08:20, used on 89 of 357 flights, with 08:25 (89 flights) and 08:30 (49 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 08:2089 flights24.9%
Departs 08:2589 flights24.9%
Departs 08:3049 flights13.7%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 08:20 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 3881 runs 8 points better at 92.4%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

OO 3881 next to SEA to SMF

Every carrier on SEA to SMF combined arrived on time 81.9% of the time across 4,407 flights, so OO 3881 is 11 points ahead of it. SkyWest flew 1,941 flights on the same city pair under all its flight numbers, including this one, and those ran 89.3% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 13 points.

OO 3881 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 3881thin sample	357	92.4%	84 min	0.00%	A+
All SkyWest Airlines on SEA–SMF	1,941	89.3%	62 min	0.26%	A+
All carriers on SEA–SMF	4,407	81.9%	50 min	0.41%	B+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 3881 quarter by quarter

OO 3881 did not run the same all year. Its best quarter was Apr–Jun 2026 at 97.8% on time and its weakest Jan–Mar 2026 at 87.5%, a swing of 10 points on roughly 89 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Jul–Sep 202590 flights94.4%
Oct–Dec 202586 flights89.5%
Jan–Mar 202690 flights87.5%
Apr–Jun 202691 flights97.8%

Scale runs 80% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, OO 3881 ranged from 86.5% on Wednesday to 96.2% on Thursday. With about 51 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why OO 3881 runs late

One category carries most of the weight here. Carrier accounts for 64% of the 2,257 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

Carrier
64%
Extreme weather
33%
National Airspace System
3%

Extreme weather accounts for 33% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the quarterly figures above are the more useful view of the risk. The national share is 6%, so this operation carries roughly 5.2 times the usual weather exposure. The split is drawn from 2,257 delay minutes reported on OO 3881.

Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 3.4% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

The 605 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The same number turns up on one other city pair in the data, including SMF to SEA (205), but none flew often enough under OO 3881 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SEA to SMF only.

One caution: this is a thin sample. 357 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking OO 3881

For a booking, OO 3881 has one of the better records a US domestic flight can show: 92.4% on time and 0.00% cancelled. That is a base rate, not a promise about any single day.

Where to go next

A flight number here means SkyWest Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures