Flight number record

OO 3688

SkyWest Airlines · Seattle to Boise

Route: SEA → BOI
Departs: 16:20
Flights: 361
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 3688, 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 3688 earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 55 minutes. That rests on 361 flights, with a median arrival 9 minutes early.

Set against the rest of the country, OO 3688's record is 9 points better than the US average of 77.6%. That gap is worth roughly 85 fewer late arrivals for every thousand flights.

On time

86.1%

Arrivals under 15 minutes late, of 360 completed flights

Avg delay

53 min

Across delayed arrivals only, not all flights

Cancelled

0.28%

National rate is 1.81%

1 hour+ late

4.4%

National rate is 8.1%

These figures cover 361 flights between July 2025 and June 2026. The median arrival is 9 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 3688 flies

OO 3688 flies SEA to BOI without a single fixed slot. Its most common scheduled departure was 16:20, used on 71 of 361 flights, with 15:40 (56 flights) and 15:59 (38 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 16:2071 flights19.7%
Departs 15:4056 flights15.5%
Departs 15:5938 flights10.5%

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 16:20 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and OO 3688 runs 14 points better at 86.1%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

OO 3688 next to SEA to BOI

Every carrier on SEA to BOI combined arrived on time 85.8% of the time across 3,972 flights, so OO 3688 is about level with it. SkyWest flew 3,081 flights on the same city pair under all its flight numbers, including this one, and those ran 87.2% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 7 points.

OO 3688 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 3688thin sample	361	86.1%	53 min	0.28%	A+
All SkyWest Airlines on SEA–BOI	3,081	87.2%	52 min	0.19%	A+
All carriers on SEA–BOI	3,972	85.8%	49 min	0.25%	A+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 3688 quarter by quarter

OO 3688 did not run the same all year. Its best quarter was Oct–Dec 2025 at 92.0% on time and its weakest Jan–Mar 2026 at 82.0%, a swing of 10 points on roughly 90 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 202592 flights88.0%
Oct–Dec 202588 flights92.0%
Jan–Mar 202690 flights82.0%
Apr–Jun 202691 flights82.4%

Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, OO 3688 did best on Saturday at 94.1% on time and worst on Wednesday at 78.8%. Each day rests on about 52 flights, so a gap of 15 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 3688 runs late

One category carries most of the weight here. Carrier accounts for 65% of the 2,632 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
65%
Extreme weather
27%
National Airspace System
8%

Extreme weather accounts for 27% 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 4.3 times the usual weather exposure. The split is drawn from 2,632 delay minutes reported on OO 3688.

Cancellations are rare at 0.28%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is 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 4.4% 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 same number turns up on one other city pair in the data, including BOI to SEA (225), but none flew often enough under OO 3688 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SEA to BOI only.

One caution: this is a thin sample. 361 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 3688

For a booking, OO 3688 has one of the better records a US domestic flight can show: 86.1% on time and 0.28% 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