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DelayAtlas

Route reliability record

SEABZN

Seattle to Bozeman

Flights
1,572
Period
July 2025 to June 2026
Distance
543 mi
Carriers
3
B+GRADE

This route 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 50 minutes on average. That is a workable record, not a spotless one. That rests on 1,572 SEA to BZN flights, of which SkyWest Airlines flew 948 at 87.4% on time.

Best time to fly SEA to BZN: a 5pm–8pm departure, ideally on a Saturday. Flights in that window arrived on time 92.4% of the time and Saturday flights 85.1%, against 82.8% for the route overall.

Set against the rest of the country, this route's record is 5 points better than the US average of 77.6%. That gap is worth roughly 52 fewer late arrivals for every thousand flights.

Key figures

On time

82.8%

Arrivals under 15 minutes late, of 1,562 completed flights

Avg delay

51 min

Across delayed arrivals only, not all flights

Cancelled

0.51%

National rate is 1.81%

Best carrier

SkyWest

87.4% on time across 948 flights

These figures cover 1,572 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

Which airline is most reliable on SEA to BZN

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 87.4% of the time; Alaska Airlines manages 75.9%. Sample sizes sit next to every figure, because a two-point gap across 623 flights means less than a ten-point one.

On-time performance by carrier on SEA to BZN
AirlineFlightsOn timeAvg delayCancelledGrade
Delta Air Linesthin sample1100.0%0.00%A+
SkyWest Airlines94887.4%51 min0.21%A+
Alaska Airlines62375.9%51 min0.96%B+

SkyWest leads Alaska by 12 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Best ways to make this trip

The most reliable ways to fly Seattle to Bozeman

Every airline on this route, ranked by how often a scheduled flight actually operated and arrived on time, with its best departure time and most punctual flight number. No nearby airport pair beat these.

Most reliable ways to fly from SEA to BZN
OptionAirlineSuccessOn timeCancelledBest departureMost punctual flight
1. SEABZNSeattle to BozemanSkyWest Airlines87.2%87.4%0.21%5pm–8pm, Sat
2. SEABZNSeattle to BozemanAlaska Airlines75.2%75.9%0.96%8pm–5am, Sun

Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.

Plan this trip by month, day and time

Departure window

The best time of day to leave

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 points, against 12 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

  • 5am–8am
  • 8am–11am183 flights88.4%
  • 11am–2pm585 flights80.9%
  • 2pm–5pm255 flights76.0%
  • 5pm–8pm210 flights92.4%
  • 8pm–5am339 flights82.5%

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

The 5pm–8pm window is the strongest at 92.4% on time. The full set of windows spans 16 points.

Across the year

When delays peak on this route

This route's year swings by 14 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.

On-time rate by calendar month81J87F85M84A80M82J76J81A88S85O90N81D
Darker means more delays. Figures are on-time percentages.November best, July worst

July is the worst month at 75.5% on time, 14 points below November, the best at 89.5%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. December was the busiest month here, with 162 flights.

Across the week, Saturday is the strongest day at 85.1% on time and Thursday the weakest at 79.9%. 5 points is a smaller lever than departure hour, but it is free.

On-time rate by day of the week83.3Mon85.0Tue84.4Wed79.9Thu81.3Fri85.1Sat81.1Sun
Monday: 83.3 percent on time. Tuesday: 85.0 percent on time. Wednesday: 84.4 percent on time. Thursday: 79.9 percent on time. Friday: 81.3 percent on time. Saturday: 85.1 percent on time. Sunday: 81.1 percent on time

Delay causes

Why this route gets delayed

One category carries most of the weight here. Carrier accounts for 49% of the 14,000 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.

  • Carrier
    49%
  • Late-arriving aircraft
    24%
  • National Airspace System
    14%
  • Extreme weather
    13%
  • Security
    0%

Extreme weather accounts for 13% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.1 times the usual weather exposure. The split is drawn from 13,612 reported delay minutes.

The largest share of delay minutes, 49%, 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 6,624 of the 14,000 delay minutes reported here.

Cancellations are rare at 0.51%, 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 actually costs

Badly late arrivals are rare here: only 4.4% 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 543 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 runs 84.4% on time across 1,571 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

The sample behind these figures is 1,572 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.

Work out the risk of missing a connection in BZN after this flight

What to do with this

Booking this route

Put together: the calendar is the biggest lever here, not the carrier or the hour. November runs 89.5% on time and July 75.5%, a swing of 14 points. If the dates move at all, move them out of July before you think about anything else. 1,562 completed flights over 12 months sit behind that.

Common questions

SEA to BZN questions

How often is SEA to BZN delayed?

About one flight in six arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 17.2% of the 1,572 flights in this analysis, against 22.4% nationally. Delayed flights are late by about 50 minutes on average.

Which airline is most reliable on SEA to BZN?

SkyWest Airlines leads at 87.4% on time across 948 flights. Alaska Airlines is at the other end on 75.9%, a gap of 12 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.

What time of day has the fewest delays on SEA to BZN?

The 5pm–8pm departure window is the strongest at 92.4% on time. The 2pm–5pm window is the weakest at 76.0%, 16 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.

How bad are July delays on SEA to BZN?

July is the weakest month at 75.5% on time, compared with 89.5% in November. Across the year that is 14 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Related

Where to go next

Direction matters. SEA to BZN and BZN to SEA are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

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Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.

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.