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Route · DTW → SEA · 2020–2025 BTS data

Detroit to Seattle

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), DTW to SEA (Detroit to Seattle) ranks #962 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

85%
On-time
+6 pts
vs US avg
61 min
Delay when late
11,558
Flights
#962 of 4927
Corpus placement

Cancelled

0.7%

Best Month

Feb 2024 95%

Worst Month

Dec 2025 38%

Distance

1,927 mi

Carriers

3

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 164 101 2 0 DL,AS
Nov 2025 154 43 0 0 DL,AS
Oct 2025 159 20 0 1 AS,DL
Sep 2025 176 18 0 0 DL,AS
Aug 2025 214 35 2 0 AS,DL
Jul 2025 228 53 5 0 AS,DL
Jun 2025 218 46 1 0 AS,DL
May 2025 197 17 0 0 AS,DL
Apr 2025 147 21 0 0 DL,AS
Mar 2025 141 18 0 0 AS,DL
Feb 2025 108 23 1 0 AS,DL
Jan 2025 122 19 0 0 AS,DL
Dec 2024 153 21 0 0 AS,DL
Nov 2024 147 12 0 0 AS,DL
Oct 2024 161 19 0 0 AS,DL
Sep 2024 208 20 1 1 AS,DL
Aug 2024 223 49 1 1 AS,DL
Jul 2024 234 39 9 1 AS,DL
Jun 2024 222 81 0 0 AS,DL
May 2024 194 52 0 0 AS,DL
Apr 2024 146 18 1 0 AS,DL
Mar 2024 142 21 0 1 AS,DL
Feb 2024 120 6 0 0 AS,DL
Jan 2024 131 28 7 0 AS,DL

DTW–SEA seasonal on-time pattern

Best: October (90.7%) · weakest: December (74.2%)

70%75%80%85%90%95% JanFebMarAprMayJunJulAugSepOctNovDec 74.2%

Strongest calendar month

October

90.7% on-time · ~160 flights/mo

Busiest calendar month

July

~205 flights/mo avg

Weakest calendar month

December

74.2% on-time · ~153 flights/mo

Cancellation Rate

0.7%

30 of 4,109 flights

Diversion Rate

0.1%

5 of 4,109 flights

Explore origin & destination

On-time and delay data for the airports this route connects.

DTW - Detroit

Full on-time, delay-cause, and seasonal performance for Detroit, MI.

DTW on-time profile

SEA - Seattle

Full on-time, delay-cause, and seasonal performance for Seattle, WA.

SEA on-time profile

Compare the two airports

See DTW and SEA side by side on delays, cancellations, and reliability.

Compare DTW vs SEA

Origin-hub reliability standing

Among DTW's stronger departures

DTW → SEA posts a 85% on-time rate, landing in the ≥85% band with 34 of 94 BTS-tracked routes leaving Detroit. The same hub also shows 60 mid-band and 0 challenged departures · fleet-wide on-time rank #1209 of 4927 (highest on-time = #1).

What the Data Says About DTW to SEA

Detroit to Seattle (DTW to SEA) is one of the more dependable pairings in the BTS On-Time Performance dataset: a 85% on-time rate across 11,558 flights, with delays that do happen averaging 60.8 minutes. The corridor runs roughly 1,927 miles and is served by 3 carriers. Over the most recent 24 months, 30 of 4,109 flights were cancelled (0.7%) and 5 diverted (0.1%).

The monthly split is wide on this route: Feb 2024 posted the strongest performance at 95% on-time, while Dec 2025 came in at just 38% - a 57-point swing worth factoring into travel timing.

On the multi-year calendar, DTW–SEA peaks in October at 90.7% on-time while July carries the heaviest traffic (~205 flights per month) ; the softest month is December at 74.2%, a 16.5-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does DTW to SEA rank among US routes by traffic? ▼
According to PlainFlights' route traffic ranking, DTW to SEA ranks #962 of 4927 tracked domestic routes by total flights (most flights = #1). That ordinal matches our busiest-routes listing (total_flights DESC). See /methodology#corpus-placement for the exact sort basis.
How often are flights delayed from DTW to SEA? ▼
Flights from Detroit to Seattle have a 85% on-time rate based on 11,558 flights. The average delay is 60.8 minutes. The best recent month was Feb 2024 with 95% on-time.
What is the cancellation rate for DTW to SEA? ▼
Over the last 24 months, 0.7% of flights on this route were cancelled (30 of 4,109 flights) and 0.1% were diverted.
How far is the flight from DTW to SEA? ▼
The flight distance from Detroit (DTW) to Seattle (SEA) is approximately 1,927 miles. This route is served by 3 carriers.
When is the best time to fly from DTW to SEA? ▼
The best recent month for on-time performance was Feb 2024 (95% on-time). The worst was Dec 2025 (38% on-time). Consider booking during months with historically better performance.

Airports on this route

DTW Airport

Detroit
SEA Airport

Seattle
Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Read our methodology - how this data is sourced, computed, and verified.

Using DTW–SEA data

DTW–SEA runs 6 pts above the national 79% average; the remaining risk is month-to-month swing and carrier mix, not a weak headline rate.

  • Compare DTW and SEA airport profiles: delay causes and top routes differ even on the same corridor. DTW airport
  • If your dates flex, October (90.7% on-time) beats December (74.2%) on this corridor. Seasonal chart
  • 4 other routes post a similar 85% on-time rate; compare before you commit to this pairing. Similar routes

On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.