Flight number record

OO 3678

SkyWest Airlines · Boise to Seattle

Route: BOI → SEA
Departs: 07:30
Flights: 334
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 3678, 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 3678 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 about 45 minutes. That rests on 334 flights, with a median arrival 19 minutes early.

Set against the rest of the country, OO 3678's record is 15 points better than the US average of 77.6%. That gap is worth roughly 149 fewer late arrivals for every thousand flights.

On time

92.5%

Arrivals under 15 minutes late, of 332 completed flights

Avg delay

45 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

2.1%

National rate is 8.1%

These figures cover 334 flights between July 2025 and June 2026. The median arrival is 19 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 3678 flies

OO 3678 flies BOI to SEA without a single fixed slot. Its most common scheduled departure was 07:30, used on 213 of 334 flights, with 07:25 (39 flights) and 07:40 (34 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 07:30213 flights63.8%
Departs 07:2539 flights11.7%
Departs 07:4034 flights10.2%

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 07:30 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and OO 3678 runs 3 points better at 92.5%. 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 3678 next to BOI to SEA

Every carrier on BOI to SEA combined arrived on time 85.7% of the time across 3,820 flights, so OO 3678 is 7 points ahead of it. SkyWest flew 2,929 flights on the same city pair under all its flight numbers, including this one, and those ran 86.2% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 14 points.

OO 3678 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 3678thin sample	334	92.5%	45 min	0.00%	A+
All SkyWest Airlines on BOI–SEA	2,929	86.2%	58 min	0.27%	A+
All carriers on BOI–SEA	3,820	85.7%	56 min	0.39%	A+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 3678 quarter by quarter

Quarter by quarter OO 3678 held fairly steady: 96.7% in Jul–Sep 2025, 92.3% in Oct–Dec 2025, 89.9% in Jan–Mar 2026 and 90.0% in Apr–Jun 2026. A spread of 7 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights96.7%
Oct–Dec 202592 flights92.3%
Jan–Mar 202690 flights89.9%
Apr–Jun 202660 flights90.0%

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

By weekday, OO 3678 ranged from 89.1% on Thursday to 95.8% on Monday. With about 48 flights behind each day, a spread of 7 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why OO 3678 runs late

One category carries most of the weight here. Carrier accounts for 58% of the 1,114 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
58%
National Airspace System
22%
Extreme weather
19%

Extreme weather accounts for 19% 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 3.1 times the usual weather exposure. The split is drawn from 1,114 delay minutes reported on OO 3678.

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 2.1% 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 four other city pairs in the data, including CLE to DTW (25), DTW to CLE (25) and SEA to BOI (24), but none flew often enough under OO 3678 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to BOI to SEA only.

One caution: this is a thin sample. 334 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 3678

For a booking, OO 3678 has one of the better records a US domestic flight can show: 92.5% 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