ON TIMEBOARD

IND → SEA on time

Indianapolis (Indianapolis, IN) to Seattle-Tacoma (Seattle, WA). Every scheduled flight, September 2025 to August 2026.

On time
75%
arrived < 15 min late
Cancelled
1.4%
567 flights
Typical arrival
−2 min
median vs schedule
When late
+49 min
average delay
Flights / day
2
1 airline

75% of flights from Indianapolis to Seattle arrived on time over the past 12 months. That is worse than the typical U.S. route. The 7 a.m. departures ran on time 79% of the time; the 7 p.m. ones 65%. 8% of flights arrived more than an hour late or not at all.

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for IND → SEA: when a flight was late, it was under 45 minutes late 63% of the time. About 1 in 16 flights landed an hour or more late; 1.4% were cancelled outright.

Share of all 567 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
Alaska Airlines56775%1.4%−2 min6.3%+49 minAlaska Airlines

Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.

Best time of day to fly

On-time rate by scheduled departure hour (local time at IND). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%6 a.m. departures: too few flights (33 flights)6a7 a.m. departures: 79% on time (237 flights)797a8 a.m. departures: too few flights8a9 a.m. departures: too few flights9a10 a.m. departures: too few flights (1 flights)10a11 a.m. departures: too few flights11anoon departures: too few flights12p1 p.m. departures: too few flights1p2 p.m. departures: too few flights2p3 p.m. departures: too few flights3p4 p.m. departures: too few flights4p5 p.m. departures: too few flights (82 flights)5p6 p.m. departures: too few flights (79 flights)6p7 p.m. departures: 65% on time (135 flights)657p
IND → SEA, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

Last flight of the day

On IND → SEA, each airline's last flight of the day was cancelled 0.5% of the time, against 1.4% for its earlier flights, so here the last flight is actually the safer one. It arrived 3+ hours late 0.0% of the time (earlier flights: 0.5%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
Alaska Airlines5:19 p.m.0.5%0.0%1.4%first flight 7:04 a.m.

Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.

By month

Each calendar month pooled over 2023–2026. Best: October (89%). Worst: June (60%).

40%70%100%Jan: too few flights (82 flights)JanFeb: too few flights (75 flights)FebMar: 71% on time (100 flights)71MarApr: 78% on time (126 flights)78AprMay: 76% on time (179 flights)76MayJun: 60% on time (180 flights)60JunJul: 78% on time (184 flights)78JulAug: 70% on time (182 flights)70AugSep: 75% on time (166 flights)75SepOct: 89% on time (126 flights)89OctNov: 85% on time (106 flights)85NovDec: 74% on time (117 flights)74Dec

By day of week

DayFlightsOn timeCancelled
Monday90——
Tuesday69——
Wednesday75——
Thursday84——
Friday88——
Saturday78——
Sunday83——

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Late inbound plane 51%Airline (crew, maintenance, ops) 22%Air traffic & airport (NAS) 20%Severe weather 6%

Cancellations: weather 5 · airline 3

Month by month

Not enough months with data to draw a trend.

Flight numbers on this route

Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.

FlightDepartsFlightsOn timeCancelledTypical arrivalOperated by
AS 6257:04 a.m.16179%0.6%−3 minAlaska Airlines
AS 5005:19 p.m.32070%1.6%−1 minAlaska Airlines

Questions

How often are flights from IND to SEA on time?

75% of 567 scheduled flights from Indianapolis, IN to Seattle, WA arrived within 15 minutes of schedule between September 2025 and August 2026. 1.4% were cancelled.

What is the best time of day to fly IND to SEA?

Flights scheduled to leave at 7 a.m. were the most reliable (79% on time). The 7 p.m. departures were the least (65%).

What month has the most delays from IND to SEA?

June (60% on time). The best month is October (89%), over 2023–2026.

Is the last flight of the day from IND to SEA more likely to be cancelled?

No, the opposite. Each airline's last IND–SEA flight of the day was cancelled 0.5% of the time over the past year, against 1.4% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.