Flight number record

AS 329

Alaska Airlines · Chicago to Seattle

Route: ORD → SEA
Departs: 10:00
Flights: 270
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s AS 329, check with Alaska Airlines.

AS 329 sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 8 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 270 flights, with a median arrival 1 minute late.

The national on-time rate over the same period is 77.6%, so AS 329 runs 8 points behind the country as a whole. Across a thousand flights that is about 79 extra late arrivals.

On time

69.7%

Arrivals under 15 minutes late, of 267 completed flights

Avg delay

65 min

Across delayed arrivals only, not all flights

Cancelled

1.11%

National rate is 1.81%

1 hour+ late

8.2%

National rate is 8.1%

These figures cover 270 flights between July 2025 and June 2026. Beyond the headline rate, 8.2% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Schedule

When AS 329 flies

AS 329 flies ORD to SEA without a single fixed slot. Its most common scheduled departure was 10:00, used on 162 of 270 flights. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 10:00162 flights60.0%

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 10:00 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and AS 329 runs 14 points worse at 69.7%. 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

AS 329 next to ORD to SEA

Every carrier on ORD to SEA combined arrived on time 68.5% of the time across 5,572 flights, so AS 329 is about level with it. Alaska flew 1,799 flights on the same city pair under all its flight numbers, including this one, and those ran 67.5% on time. Across its whole network Alaska Airlines managed 79.1%, which this flight trails by 9 points.

AS 329 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
AS 329thin sample	270	69.7%	65 min	1.11%	C
All Alaska Airlines on ORD–SEA	1,799	67.5%	63 min	1.67%	C
All carriers on ORD–SEA	5,572	68.5%	64 min	1.45%	C
Alaska Airlines, whole network	293,372	79.1%	52 min	1.28%	B

Across the year

AS 329 quarter by quarter

AS 329 did not run the same all year. Its best quarter was Jul–Sep 2025 at 80.4% on time and its weakest Oct–Dec 2025 at 58.6%, a swing of 22 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 flights80.4%
Oct–Dec 202588 flights58.6%
Jan–Mar 202621 flights—
Apr–Jun 202669 flights67.2%

Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.

By weekday, AS 329 ranged from 65.8% on Tuesday to 75.8% on Sunday. With about 39 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 AS 329 runs late

Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 5,231 reported delay minutes.

National Airspace System
33%
Late-arriving aircraft
30%
Extreme weather
19%
Carrier
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 3.0 times the usual weather exposure. The split is drawn from 5,231 delay minutes reported on AS 329.

Cancellations sit at 1.11% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

8.2% 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 about an hour, which a normal layover absorbs.

At 1,721 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

The same number turns up on one other city pair in the data, including SEA to MCI (5), but none flew often enough under AS 329 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to ORD to SEA only.

One caution: this is a thin sample. 270 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 AS 329

For a booking, read AS 329 as 69.7% on time with 1.11% cancelled over 270 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 Alaska 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