Carrier route record

DLANC→SEA

Delta Air Lines · Anchorage to Seattle

Flights: 1,630
Period: July 2025 to June 2026
Share of route: 24%
Carriers: 3

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.

Delta on ANC to SEA earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 12 points better than the national rate of 77.6%. When something does go wrong the average delay runs close to two hours. That rests on 1,630 flights, with a median arrival 17 minutes early.

Set against the rest of the country, Delta's ANC to SEA record is 12 points better than the US average of 77.6%. That gap is worth roughly 115 fewer late arrivals for every thousand flights.

On time

89.1%

Arrivals under 15 minutes late, of 1,618 completed flights

Avg delay

105 min

Across delayed arrivals only, not all flights

Cancelled

0.67%

National rate is 1.81%

Whole route

85.5%

Every carrier on ANC to SEA, 6,681 flights

These figures cover 1,630 flights between July 2025 and June 2026. The median arrival is 17 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.

Carrier by carrier

Delta against every carrier on ANC to SEA

Delta flew 1,630 of the 6,681 flights on ANC to SEA, about 24% of it. Its 89.1% on time is 4 points better than the route as a whole, which runs 85.5%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from Delta at 89.1% to Hawaiian at 27.9%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

On-time performance by carrier on ANC to SEA
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines (this page)	1,630	89.1%	105 min	0.67%	A+
Alaska Airlines	4,926	85.7%	52 min	1.24%	A
Hawaiian Airlinesthin sample	125	27.9%	74 min	2.40%	F

Flight by flight

Delta flight numbers on ANC to SEA

Departure window

When Delta runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 15 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am365 flights89.8%
8am–11am65 flights95.4%
11am–2pm359 flights90.4%
2pm–5pm317 flights88.0%
5pm–8pm178 flights80.2%
8pm–5am346 flights91.6%

Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.

Book the morning departure. Flights leaving between 8am–11am arrive on time 95.4% of the time, against 80.2% for the evening window. That is 15 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 365 flights scheduled in it.

Across the year

Delta on ANC to SEA through the year

Darker means more delays. Figures are on-time percentages.May best, December worst

December is the weak month at 78.2% on time, against 96.9% in May. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. July was the busiest month here, with 171 flights.

Across the week, Friday is the strongest day at 91.6% on time and Monday the weakest at 84.2%. 7 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Delta runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 49% of the 18,000 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.

Late-arriving aircraft
49%
Carrier
36%
Extreme weather
7%
National Airspace System
7%
Security
0%

49% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 18,000 reported delay minutes here, that single category outweighs weather by 7 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 18,405 reported delay minutes.

The largest share of delay minutes, 36%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 6,576 of the 18,000 delay minutes reported here.

Cancellations are rare at 0.67%, below the national 1.81% 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 stage length

What a delay here costs

Badly late arrivals are rare here: only 4.3% land an hour or more behind schedule, against 8.1% 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 1,448 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg is a different operation and performs like one: it runs 77.9% on time across 1,630 flights, 11 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 11 points of difference.

The sample behind these figures is 1,630 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.

What to do with this

Booking Delta on ANC to SEA

Put together: the calendar is the biggest lever here, not the carrier or the hour. May runs 96.9% on time and December 78.2%, a swing of 19 points. If the dates move at all, move them out of December before you think about anything else. 1,618 completed flights over 12 months sit behind that.

Where to go next

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