Carrier route record
DLMSP→SEA
Delta Air Lines · Minneapolis to Seattle
- Flights
- 1,737
- Period
- July 2025 to June 2026
- Share of route
- 65%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on MSP to SEA lands a B+, 5 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 1,737 flights, with a median arrival 6 minutes early.
Set against the rest of the country, Delta's MSP to SEA record is 5 points better than the US average of 77.6%. That gap is worth roughly 45 fewer late arrivals for every thousand flights.
Key figures
On time
82.1%
Arrivals under 15 minutes late, of 1,716 completed flights
Avg delay
60 min
Across delayed arrivals only, not all flights
Cancelled
0.92%
National rate is 1.81%
Whole route
81.1%
Every carrier on MSP to SEA, 2,690 flights
These figures cover 1,737 flights between July 2025 and June 2026. The median arrival is 6 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 MSP to SEA
Delta flew 1,737 of the 2,690 flights on MSP to SEA, most of the route. Its 82.1% on time is about level with the route as a whole at 81.1%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Delta at 82.1% to Alaska at 79.4%.
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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines (this page) | 1,737 | 82.1% | 60 min | 0.92% | B+ |
| Alaska Airlines | 953 | 79.4% | 56 min | 1.26% | B |
Flight by flight
Delta flight numbers on MSP 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 24 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–8am98 flights96.9%
- 8am–11am551 flights87.5%
- 11am–2pm212 flights84.0%
- 2pm–5pm313 flights75.4%
- 5pm–8pm341 flights73.1%
- 8pm–5am222 flights83.6%
Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 96.9% of the time, against 73.1% for the evening window. That is 24 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 551 flights scheduled in it.
Across the year
Delta on MSP to SEA through the year
December is the weak month at 56.6% on time, against 95.9% in September. 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 172 flights.
Across the week, Tuesday is the strongest day at 86.0% on time and Sunday the weakest at 78.7%. 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. Carrier accounts for 52% 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.
- 52%Carrier
- 24%National Airspace System
- 21%Late-arriving aircraft
- 4%Extreme weather
The largest share of delay minutes, 52%, 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 9,564 of the 18,000 delay minutes reported here. The split is drawn from 18,489 reported delay minutes.
Cancellations sit at 0.92% against a national 1.81%, which is ordinary. Diversions add another 0.29%.
Connections and stage length
What a delay here costs
5.4% 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.
The 1,399 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 88.5% on time across 1,736 flights, 6 points above 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 6 points of difference.
The sample behind these figures is 1,737 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 MSP to SEA
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 95.9% on time and December 56.6%, a swing of 39 points. If the dates move at all, move them out of December before you think about anything else. 1,716 completed flights over 12 months sit behind that.
Related
Where to go next
- MSP to SEA, every carrier
- Delta on SEA to MSP, the return leg
- Alaska Airlines on MSP to SEA79.4%
- Delta Air Lines network-wide record
- Minneapolis-St Paul International (MSP) delay statistics
- Seattle-Tacoma International (SEA) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
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.