Flight number record
AS 645
Alaska Airlines · Phoenix to Seattle
- Route
- PHX → SEA
- Departs
- 07:00
- Flights
- 330
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s AS 645, check with Alaska Airlines.
AS 645 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 8 points better than the national rate of 77.3%. When something does go wrong the average delay runs about 45 minutes. That rests on 330 flights, with a median arrival 5 minutes early.
Set against the rest of the country, AS 645's record is 8 points better than the US average of 77.3%. That gap is worth roughly 78 fewer late arrivals for every thousand flights.
Key figures
On time
85.1%
Arrivals under 15 minutes late, of 328 completed flights
Avg delay
46 min
Across delayed arrivals only, not all flights
Cancelled
0.30%
National rate is 1.89%
1 hour+ late
2.4%
National rate is 8.3%
These figures cover 330 flights between September 2025 and August 2026. The median arrival is 5 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 645 flies
AS 645 flies PHX to SEA without a single fixed slot. Its most common scheduled departure was 07:00, used on 83 of 330 flights, with 07:20 (79 flights) and 08:00 (71 flights) next.
- Departs 07:0083 flights25.2%
- Departs 07:2079 flights23.9%
- Departs 08:0071 flights21.5%
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 07:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and AS 645 runs 4 points worse at 85.1%. 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 645 next to PHX to SEA
Every carrier on PHX to SEA combined arrived on time 82.2% of the time across 7,202 flights, so AS 645 is 3 points ahead of it. Alaska flew 2,886 flights on the same city pair under all its flight numbers, including this one, and those ran 84.4% on time. Across its whole network Alaska Airlines managed 79.7%, which this flight beats by 5 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| AS 645thin sample | 330 | 85.1% | 46 min | 0.30% | A+ |
| All Alaska Airlines on PHX–SEA | 2,886 | 84.4% | 56 min | 0.76% | B+ |
| All carriers on PHX–SEA | 7,202 | 82.2% | 56 min | 0.69% | B+ |
| Alaska Airlines, whole network | 309,844 | 79.7% | 52 min | 1.20% | B |
Across the year
AS 645 quarter by quarter
AS 645 did not run the same all year. Its best quarter was Jul–Sep 2025 at 93.3% on time and its weakest Jul–Sep 2026 at 70.5%, a swing of 23 points on roughly 66 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 flights93.3%
- Oct–Dec 202590 flights87.8%
- Jan–Mar 202685 flights86.9%
- Apr–Jun 202663 flights88.9%
- Jul–Sep 202662 flights70.5%
Scale runs 60% to 100%.
By weekday, AS 645 did best on Tuesday at 93.6% on time and worst on Thursday at 79.2%. Each day rests on about 47 flights, so a gap of 14 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late AS 645 runs when it is late
AS 645 often beats the schedule: 92 of 328 completed flights, 28%, arrived 15 minutes or more early. Most of the lateness is short. 25 of the 49 late arrivals were under half an hour behind, and 8 reached an hour or more.
- 15+ min early92 flights28.0%
- Within 15 min187 flights57.0%
- 15–29 min late25 flights7.6%
- 30–59 min late16 flights4.9%
- 1–2 hours late4 flights1.2%
- 2+ hours late4 flights1.2%
Scale runs 0% to 100%.
Share of 328 completed flights by arrival against schedule.
7 of 40 late departures made up the time and arrived on time, 18% of them. 16 flights left on time and still arrived late.
The worst days
Worst days for AS 645
The latest arrival of the period was on 31 December 2025, 3 hours 44 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on five of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 31 December 2025 | 3 hours 44 minutes | Carrier |
| 10 November 2025 | 3 hours 22 minutes | Carrier |
| 24 April 2026 | 2 hours 44 minutes | Carrier |
| 26 December 2025 | 2 hours 20 minutes | Carrier |
| 20 June 2026 | 1 hour 39 minutes | Carrier |
Delay causes
Why AS 645 runs late
Carrier accounts for 50% of the 2,232 delay minutes carriers reported here, and the remaining four split what is left.
- 50%Carrier
- 45%National Airspace System
- 3%Late-arriving aircraft
- 1%Extreme weather
The largest share of delay minutes, 50%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,122 of the 2,232 delay minutes reported here. The split is drawn from 2,232 delay minutes reported on AS 645.
Cancellations are rare at 0.30%, below the national 1.89% 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 2.4% 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.
The 1,107 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.
Every one of the 330 flights under AS 645 in the data flew PHX 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. 330 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 645
For a booking, AS 645 has one of the better records a US domestic flight can show: 85.1% on time and 0.30% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- PHX to SEA, every carrier and departure
- SEA to PHX, the return direction
- Delta Air Lines 2419 on the same route92.8%
- Alaska Airlines 637 on the same route84.0%
- Alaska Airlines 603 on the same route87.2%
- Alaska Airlines 611 on the same route81.5%
- Delta Air Lines 2444 on the same route94.2%
- Phoenix Sky Harbor International (PHX) 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.