Route reliability record
MSO→SLC
Missoula to Salt Lake City
- Flights
- 1,059
- Period
- September 2025 to August 2026
- Distance
- 436 mi
- Carriers
- 2
This route 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 14 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 1,059 MSO to SLC flights, of which SkyWest Airlines flew 592 at 91.8% on time.
Best time to fly MSO to SLC: a 5am–8am departure, ideally on a Monday. Flights in that window arrived on time 91.4% of the time and Monday flights 95.0%, against 91.2% for the route overall.
Set against the rest of the country, this route's record is 14 points better than the US average of 77.3%. That gap is worth roughly 139 fewer late arrivals for every thousand flights.
Key figures
On time
91.2%
Arrivals under 15 minutes late, of 1,047 completed flights
Avg delay
75 min
Across delayed arrivals only, not all flights
Cancelled
0.94%
National rate is 1.89%
Best carrier
SkyWest
91.8% on time across 592 flights
These figures cover 1,059 flights between September 2025 and August 2026. The median arrival is 12 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.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Which airline is most reliable on MSO to SLC
The two carriers here are closely matched: about a point separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 592 | 91.8% | 56 min | 1.35% | A |
| Delta Air Lines | 467 | 90.5% | 96 min | 0.43% | A+ |
No carrier stands out. SkyWest tops the table at 91.8%, about a point clear of the bottom, which is inside the range this kind of sample moves year to year.
Flight by flight
Flights on MSO to SLC
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Best ways to make this trip
The most reliable ways to fly Missoula to Salt Lake City
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.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. MSO → SLCMissoula to Salt Lake City | SkyWest Airlines | 90.6% | 91.8% | 1.35% | 11am–2pm, Thu | OO 4112 13:13 |
| 2. MSO → SLCMissoula to Salt Lake City | Delta Air Lines | 90.1% | 90.5% | 0.43% | 5am–8am, Mon | DL 2795 05:30 |
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.
Departure window
The best time of day to leave
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 1,059 flights.
- 5am–8am360 flights91.4%
- 8am–11am—
- 11am–2pm354 flights91.0%
- 2pm–5pm5 flights—
- 5pm–8pm340 flights91.1%
- 8pm–5am—
Scale runs 85% to 95%. Rows with fewer than 30 flights show a dash.
The 5am–8am window is the strongest at 91.4% on time. The full set of windows spans half a point.
Explore
Filter MSO to SLC by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On MSO to SLC, the best departure window is 5am–8am at 91.4% on time and the worst is 11am–2pm at 91.0%, a narrow gap of 0.4 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am91.4%
- 8–11am—
- 11am–2pm91.0%
- 2–5pm—
- 5–8pm91.1%
- 8pm–5am—
best all US flightsScale 60% to 95%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 16 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.
Delays peak in March, when the on-time rate falls to 83.3%. June is the strongest month at 98.9%. Moving a flexible trip across that boundary buys 16 points. May was the busiest month here, with 93 flights.
Across the week, Monday is the strongest day at 95.0% on time and Wednesday the weakest at 86.5%, a spread of 9 points.
Delay causes
Why this route gets delayed
Carrier accounts for 46% of the 6,871 delay minutes carriers reported here, and the remaining four split what is left.
- 46%Carrier
- 27%Extreme weather
- 17%Late-arriving aircraft
- 10%National Airspace System
Extreme weather accounts for 27% 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 4.6 times the usual weather exposure. The split is drawn from 6,871 reported delay minutes.
The largest share of delay minutes, 46%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 3,178 of the 6,871 delay minutes reported here.
Cancellations sit at 0.94% against a national 1.89%, which is ordinary. Diversions add another 0.19%.
Connections and stage length
What a delay here actually costs
Badly late arrivals are rare here: only 2.8% land an hour or more behind schedule, against 8.3% 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.
At 436 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg runs 88.7% on time across 1,059 flights, within 3 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 1,059 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
Work out the risk of missing a connection in SLC after this flight
What to do with this
Booking this route
Put together: treat all of this as provisional. 1,059 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 91.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 1,047 completed flights over 12 months sit behind that.
Common questions
MSO to SLC questions
How often is MSO to SLC delayed?
About one flight in twelve arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 8.8% of the 1,059 flights in this analysis, against 22.7% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on MSO to SLC?
SkyWest Airlines leads at 91.8% on time across 592 flights. Delta Air Lines is at the other end on 90.5%, a gap of about a point. 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.
Does the departure time change the odds on MSO to SLC?
Not by much in this data. Every departure window falls within half a point of the others, so there is no hour worth rearranging a trip for. The overall rate of 91.2% is the figure to plan against.
How bad are March delays on MSO to SLC?
March is the weakest month at 83.3% on time, compared with 98.9% in June. Across the year that is 16 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
- SLC to MSO — the return legseparate record
- Salt Lake City International (SLC) delay statistics
- SkyWest Airlines on MSO to SLC91.8%
- Delta Air Lines on MSO to SLC90.5%
- MSO to DEN, a related route81.1%
- DEN to SLC, a related route78.2%
- PHX to SLC, a related route83.0%
- SkyWest Airlines on-time record91.8%
- Delta Air Lines on-time record90.5%
- The most punctual routes in the US, and the least
- Worst months to fly in the US, ranked by the data
Direction matters. MSO to SLC and SLC to MSO are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed MSO to SLC’s on-time badge on your site
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, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.