Airport month record
SEAJAN
Seattle-Tacoma International in January 2026
- Departures
- 11,927
- Month
- January 2026
- National, same month
- 79.2%
- Carriers
- 8
Historical statistics for January 2026, not live status or a forecast for this year’s January. For today’s conditions at SEA, see live FAA status.
SEA in January lands a B, 2 points better than the national rate of 79.2%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That rests on 11,927 flights, of which United Airlines flew 511 at 87.9% on time.
United Airlines is the most reliable of the six carriers covered here at 87.9% on time across 511 flights.
Key figures
On time
81.6%
Arrivals under 15 minutes late, of 11,651 completed departures
Avg delay
60 min
Across delayed arrivals only, not all flights
Cancelled
1.91%
Nationally in January: 4.71%
Whole year
79.5%
SEA across all twelve months
These figures cover 11,927 departures from Seattle-Tacoma International in January 2026. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.
Against the year
January next to SEA's other months
Against SEA's own year, January ran 2 points better than the twelve-month rate of 79.5%, which makes it number seven of twelve months, best first. Cancellations are where January stands out: 1.91% of scheduled departures were called off, 2.1 times the airport's rate across the year. Either side of it, December ran 74.0% on time and February 84.4%, so a trip moved by a few weeks would have landed in a worse stretch.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| September 2025 | 14,552 | 82.9% | 50 min | 0.29% | B+ |
| October 2025 | 13,859 | 82.9% | 58 min | 1.16% | B |
| November 2025 | 12,616 | 81.9% | 58 min | 1.69% | B |
| December 2025 | 13,023 | 74.0% | 59 min | 1.02% | C |
| January 2026 (this page) | 11,927 | 81.6% | 60 min | 1.91% | B |
| February 2026 | 11,000 | 84.4% | 56 min | 0.78% | B+ |
| March 2026 | 12,830 | 80.2% | 64 min | 2.23% | B |
| April 2026 | 12,864 | 85.6% | 56 min | 0.17% | A+ |
| May 2026 | 14,564 | 82.2% | 52 min | 0.41% | B+ |
| June 2026 | 15,402 | 78.1% | 57 min | 0.48% | B+ |
| July 2026 | 16,214 | 71.8% | 57 min | 0.76% | C+ |
| August 2026 | 15,908 | 72.6% | 55 min | 0.65% | C+ |
Departure window
The best time of day to leave SEA in January
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 12,000 flights.
- 5am–8am1,425 flights87.0%
- 8am–11am2,610 flights82.6%
- 11am–2pm2,575 flights77.4%
- 2pm–5pm1,641 flights81.0%
- 5pm–8pm1,704 flights81.6%
- 8pm–5am1,972 flights82.4%
Scale runs 70% to 90%.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 77.4% on time against 87.0% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 8am–11am window is the busiest, with 2,610 flights scheduled in it.
Across the week, Wednesday is the strongest day at 86.4% on time and Monday the weakest at 78.0%, a spread of 8 points.
Carrier by carrier
Which airlines ran best at SEA in January
The choice of carrier is not cosmetic here. United Airlines arrives on time 87.9% of the time; Alaska Airlines manages 79.5%. Sample sizes sit next to every figure, because a two-point gap across 5,749 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Alaska Airlines | 5,749 | 79.5% | 47 min | 1.58% | B |
| Delta Air Lines | 2,374 | 80.8% | 70 min | 2.06% | B |
| SkyWest Airlines | 2,225 | 85.3% | 75 min | 1.66% | A |
| United Airlines | 511 | 87.9% | 94 min | 1.17% | A |
| Southwest Airlines | 490 | 87.7% | 45 min | 0.20% | A+ |
| American Airlines | 449 | 80.0% | 119 min | 9.58% | B− |
| Frontier Airlinesthin sample | 87 | 83.7% | 52 min | 1.15% | B |
| Envoy Airthin sample | 42 | 85.7% | 92 min | 0.00% | A+ |
American Airlines cancels 9.6% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Busiest routes out of SEA in January
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SEA to PHX · Phoenix | 586 | 82.6% | 53 min | 1.02% | B |
| SEA to LAX · Los Angeles | 564 | 81.4% | 60 min | 0.71% | B+ |
| SEA to SFO · San Francisco | 486 | 76.2% | 82 min | 1.23% | B |
| SEA to ANC · Anchorage | 478 | 75.5% | 51 min | 2.51% | B |
| SEA to LAS · Las Vegas | 460 | 82.0% | 50 min | 0.65% | B+ |
| SEA to GEG · Spokane | 440 | 82.5% | 52 min | 2.27% | B |
| SEA to DEN · Denver | 429 | 87.4% | 52 min | 0.23% | A+ |
| SEA to PDX · Portland | 402 | 84.8% | 62 min | 0.00% | B+ |
| SEA to DFW · Dallas-Fort Worth | 397 | 76.1% | 86 min | 9.32% | B− |
| SEA to SAN · San Diegothin sample | 334 | 80.0% | 52 min | 0.30% | B+ |
| SEA to SJC · San Josethin sample | 331 | 83.2% | 60 min | 1.21% | B |
| SEA to SNA · Santa Anathin sample | 312 | 88.3% | 50 min | 1.28% | A |
| SEA to SMF · Sacramentothin sample | 311 | 84.2% | 55 min | 0.00% | B+ |
| SEA to ORD · Chicagothin sample | 301 | 73.3% | 87 min | 1.00% | C |
| SEA to SLC · Salt Lake Citythin sample | 301 | 82.4% | 50 min | 0.00% | B+ |
| SEA to BOI · Boisethin sample | 300 | 87.0% | 64 min | 0.33% | A+ |
| SEA to HNL · Honoluluthin sample | 250 | 70.9% | 60 min | 1.20% | C |
| SEA to ATL · Atlantathin sample | 213 | 86.3% | 71 min | 0.94% | A+ |
| SEA to FAI · Fairbanksthin sample | 191 | 81.0% | 43 min | 2.62% | B |
| SEA to JFK · New Yorkthin sample | 187 | 76.5% | 61 min | 4.28% | B− |
| SEA to PSP · Palm Springsthin sample | 183 | 83.7% | 63 min | 1.64% | B |
| SEA to EUG · Eugenethin sample | 169 | 84.0% | 58 min | 3.55% | B− |
| SEA to MSP · Minneapolisthin sample | 168 | 90.4% | 65 min | 0.60% | A+ |
| SEA to ONT · Ontariothin sample | 157 | 85.3% | 52 min | 0.64% | A+ |
| SEA to OGG · Kahuluithin sample | 155 | 81.3% | 42 min | 0.00% | B+ |
Delay causes
What held SEA up in January
Carrier accounts for 44% of the 129,000 delay minutes carriers reported here, and the remaining four split what is left.
- 44%Carrier
- 27%Late-arriving aircraft
- 19%National Airspace System
- 10%Extreme weather
- 0%Security
The largest share of delay minutes, 44%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 57,000 of the 129,000 delay minutes reported here. The split is drawn from 128,689 reported delay minutes.
Cancellations sit at 1.91% against a national 4.71%, which is ordinary. Diversions add another 0.40%.
5.2% of arrivals land an hour or more late, close to the national 7.6%, so 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.
What to do with this
Flying from SEA in January
For a January trip through SEA: expect 81.6% on time and 1.91% cancelled, going by January 2026. The 5am–8am window was the strongest part of the day.
Related
Where to go next
- Seattle-Tacoma International (SEA), the whole year
- SEA in September82.9%
- SEA in October82.9%
- SEA in November81.9%
- SEA in December74.0%
- SEA in February84.4%
- SEA in March80.2%
- SEA in April85.6%
- SEA in May82.2%
- SEA in June78.1%
- SEA in July71.8%
- SEA in August72.6%
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.