Flight number record
AS 543
Alaska Airlines · Dallas-Fort Worth to Seattle
- Route
- DFW → SEA
- Departs
- 10:00
- Flights
- 295
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s AS 543, check with Alaska Airlines.
AS 543 lands a B, 5 points better than the national rate of 77.3%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about 50 minutes on average. That rests on 295 flights, with a median arrival 8 minutes early.
Set against the rest of the country, AS 543's record is 5 points better than the US average of 77.3%. That gap is worth roughly 52 fewer late arrivals for every thousand flights.
Key figures
On time
82.5%
Arrivals under 15 minutes late, of 292 completed flights
Avg delay
51 min
Across delayed arrivals only, not all flights
Cancelled
1.02%
National rate is 1.89%
1 hour+ late
3.8%
National rate is 8.3%
These figures cover 295 flights between September 2025 and August 2026. The median arrival is 8 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.
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Schedule
When AS 543 flies
AS 543 flies DFW to SEA without a single fixed slot. Its most common scheduled departure was 10:00, used on 74 of 295 flights, with 06:24 (70 flights) and 09:00 (34 flights) next.
- Departs 10:0074 flights25.1%
- Departs 06:2470 flights23.7%
- Departs 09:0034 flights11.5%
Scale runs 0% to 100%.
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 83.9%, and AS 543 runs level with that at 82.5%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
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Against the route
AS 543 next to DFW to SEA
Every carrier on DFW to SEA combined arrived on time 71.1% of the time across 5,227 flights, so AS 543 is 11 points ahead of it. Alaska flew 1,758 flights on the same city pair under all its flight numbers, including this one, and those ran 77.2% on time. Across its whole network Alaska Airlines managed 79.7%, which this flight beats by 3 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| AS 543thin sample | 295 | 82.5% | 51 min | 1.02% | B |
| All Alaska Airlines on DFW–SEA | 1,758 | 77.2% | 53 min | 1.19% | B |
| All carriers on DFW–SEA | 5,227 | 71.1% | 62 min | 1.78% | C |
| Alaska Airlines, whole network | 309,844 | 79.7% | 52 min | 1.20% | B |
Across the year
AS 543 quarter by quarter
AS 543 did not run the same all year. Its best quarter was Apr–Jun 2026 at 92.9% on time and its weakest Oct–Dec 2025 at 78.2%, a swing of 15 points on roughly 59 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 202530 flights80.0%
- Oct–Dec 202588 flights78.2%
- Jan–Mar 202676 flights83.8%
- Apr–Jun 202642 flights92.9%
- Jul–Sep 202659 flights81.4%
Scale runs 70% to 100%.
By weekday, AS 543 ranged from 77.3% on Monday to 87.8% on Wednesday. With about 42 flights behind each day, a spread of 11 points is inside normal variation, so the day you fly is not worth changing for this flight.
Arrival by arrival
How late AS 543 runs when it is late
AS 543 often beats the schedule: 103 of 292 completed flights, 35%, arrived 15 minutes or more early. The 51 late arrivals split 22 under half an hour, 18 between 30 and 60 minutes, and 11 an hour or more.
- 15+ min early103 flights35.3%
- Within 15 min138 flights47.3%
- 15–29 min late22 flights7.5%
- 30–59 min late18 flights6.2%
- 1–2 hours late7 flights2.4%
- 2+ hours late4 flights1.4%
Scale runs 0% to 100%.
Share of 292 completed flights by arrival against schedule.
13 of 51 late departures made up the time and arrived on time, 25% of them. 13 flights left on time and still arrived late.
The worst days
Worst days for AS 543
The latest arrival of the period was on 2 December 2025, 4 hours 41 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The five worst days are spread across December, July, March and November, with no single month standing out.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 2 December 2025 | 4 hours 41 minutes | Carrier |
| 8 July 2026 | 3 hours 20 minutes | Carrier |
| 13 March 2026 | 2 hours 51 minutes | National Airspace System |
| 22 December 2025 | 2 hours 3 minutes | National Airspace System |
| 24 November 2025 | 1 hour 41 minutes | Extreme weather |
Delay causes
Why AS 543 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 2,589 reported delay minutes.
- 42%National Airspace System
- 39%Carrier
- 10%Late-arriving aircraft
- 9%Extreme weather
The largest share of delay minutes, 39%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,022 of the 2,589 delay minutes reported here. The split is drawn from 2,589 delay minutes reported on AS 543.
Cancellations sit at 1.02% against a national 1.89%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
Badly late arrivals are rare here: only 3.8% land an hour or more behind schedule, against 8.3% 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.
At 1,660 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.
Every one of the 295 flights under AS 543 in the data flew DFW to SEA. The number was not reused on any other city pair, which makes this a clean record of one route.
One caution: this is a thin sample. 295 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 543
For a booking, read AS 543 as 82.5% on time with 1.02% cancelled over 295 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- DFW to SEA, every carrier and departure
- SEA to DFW, the return direction
- Delta Air Lines 804 on the same route85.0%
- American Airlines 757 on the same route72.1%
- American Airlines 727 on the same route54.8%
- Alaska Airlines 365 on the same route78.8%
- American Airlines 767 on the same route74.4%
- Alaska Airlines 415 on the same route85.1%
- Dallas/Fort Worth International (DFW) delay statistics
- Seattle-Tacoma International (SEA) delay statistics
- Alaska Airlines on-time record
- Every Alaska Airlines flight number with a record
- The most and least reliable flight numbers in the US
- Worst months to fly in the US, ranked by the data
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, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.