Flight number record

OO 3740

SkyWest Airlines · Boise to Seattle

Route: BOI → SEA
Departs: 09:00
Flights: 345
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 3740, 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 3740 lands a B+, 6 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 345 flights, with a median arrival 13 minutes early.

Set against the rest of the country, OO 3740's record is 6 points better than the US average of 77.6%. That gap is worth roughly 59 fewer late arrivals for every thousand flights.

On time

83.5%

Arrivals under 15 minutes late, of 345 completed flights

Avg delay

85 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

7.5%

National rate is 8.1%

These figures cover 345 flights between July 2025 and June 2026. The median arrival is 13 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 3740 flies

OO 3740 flies BOI to SEA without a single fixed slot. Its most common scheduled departure was 09:00, used on 166 of 345 flights, with 08:50 (59 flights) and 09:15 (35 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 09:00166 flights48.1%
Departs 08:5059 flights17.1%
Departs 09:1535 flights10.1%

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 09:00 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 3740 runs level with that at 83.5%. 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 3740 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 3740 is 2 points behind 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 5 points.

OO 3740 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 3740thin sample	345	83.5%	85 min	0.00%	B+
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 3740 quarter by quarter

Quarter by quarter OO 3740 held fairly steady: 85.7% in Jul–Sep 2025, 80.0% in Oct–Dec 2025, 81.9% in Jan–Mar 2026 and 85.7% in Apr–Jun 2026. A spread of 6 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202591 flights85.7%
Oct–Dec 202580 flights80.0%
Jan–Mar 202683 flights81.9%
Apr–Jun 202691 flights85.7%

Scale runs 70% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, OO 3740 did best on Monday at 90.0% on time and worst on Thursday at 76.0%. Each day rests on about 49 flights, so a gap of 14 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 3740 runs late

One category carries most of the weight here. Carrier accounts for 73% of the 4,869 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
73%
Extreme weather
15%
National Airspace System
13%

Extreme weather accounts for 15% 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 2.4 times the usual weather exposure. The split is drawn from 4,869 delay minutes reported on OO 3740.

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

7.5% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last an hour and a half, which a normal layover absorbs.

The same number turns up on one other city pair in the data, including SLC to SBA (16), but none flew often enough under OO 3740 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. 345 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 3740

For a booking, read OO 3740 as 83.5% on time with 0.00% cancelled over 345 flights. Those are rates from the past twelve months, not a forecast for any particular 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