Carrier route record
DLMSO→SLC
Delta Air Lines · Missoula to Salt Lake City
- Flights
- 467
- Period
- September 2025 to August 2026
- Share of route
- 44%
- Carriers
- 2
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on MSO to SLC 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 13 points better than the national rate of 77.3%. When something does go wrong the average delay runs an hour and a half. That rests on 467 flights, with a median arrival 14 minutes early.
Set against the rest of the country, Delta's MSO to SLC record is 13 points better than the US average of 77.3%. That gap is worth roughly 132 fewer late arrivals for every thousand flights.
Key figures
On time
90.5%
Arrivals under 15 minutes late, of 464 completed flights
Avg delay
96 min
Across delayed arrivals only, not all flights
Cancelled
0.43%
National rate is 1.89%
Whole route
91.2%
Every carrier on MSO to SLC, 1,059 flights
These figures cover 467 flights between September 2025 and August 2026. The median arrival is 14 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.
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Carrier by carrier
Delta against every carrier on MSO to SLC
Delta flew 467 of the 1,059 flights on MSO to SLC, about 44% of it. Its 90.5% on time is about level with the route as a whole at 91.2%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 91.8% to Delta at 90.5%.
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 |
|---|---|---|---|---|---|
| SkyWest Airlines | 592 | 91.8% | 56 min | 1.35% | A |
| Delta Air Lines (this page) | 467 | 90.5% | 96 min | 0.43% | A+ |
Flight by flight
Delta flight numbers on MSO to SLC
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.
Departure window
When Delta runs best on this route
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 467 flights.
- 5am–8am360 flights91.4%
- 8am–11am—
- 11am–2pm104 flights87.3%
- 2pm–5pm3 flights—
- 5pm–8pm—
- 8pm–5am—
Scale runs 80% to 95%. Rows with fewer than 30 flights show a dash.
The early departures do better, though not dramatically: 91.4% on time for the 5am–8am window against 87.3% for 11am–2pm. Worth taking if the schedule allows, not worth an extra connection. The 5am–8am window is the busiest, with 360 flights scheduled in it.
Across the year
Delta on MSO to SLC through the year
Delays peak in March, when the on-time rate falls to 81.7%. June is the strongest month at 100.0%. Moving a flexible trip across that boundary buys 18 points. March was the busiest month here, with 62 flights.
Across the week, Monday is the strongest day at 95.6% on time and Thursday the weakest at 84.8%, a spread of 11 points.
Arrival by arrival
How late Delta on MSO to SLC runs when it is late
Delta on MSO to SLC often beats the schedule: 225 of 464 completed flights, 48%, arrived 15 minutes or more early. The 44 late arrivals split 19 under half an hour, 10 between 30 and 60 minutes, and 15 an hour or more.
- 15+ min early225 flights48.5%
- Within 15 min195 flights42.0%
- 15–29 min late19 flights4.1%
- 30–59 min late10 flights2.2%
- 1–2 hours late7 flights1.5%
- 2+ hours late8 flights1.7%
Scale runs 0% to 100%.
Share of 464 completed flights by arrival against schedule.
9 of 38 late departures made up the time and arrived on time, 24% of them. 15 flights left on time and still arrived late.
The worst days
Worst days for Delta on MSO to SLC
The latest arrival of the period was on 28 February 2026, 9 hours 27 minutes behind schedule; most of its delay minutes were filed as extreme weather. On three of the five worst days the largest share was filed as carrier-caused (crew, maintenance, fuelling, baggage).
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 28 February 2026 | 9 hours 27 minutes | Extreme weather |
| 7 December 2025 | 7 hours 26 minutes | Carrier |
| 14 November 2025 | 7 hours 10 minutes | Carrier |
| 15 January 2026 | 6 hours 11 minutes | Carrier |
| 7 October 2025 | 5 hours 29 minutes | Late-arriving aircraft |
Delay causes
Why Delta runs late on this route
Carrier accounts for 50% of the 4,204 delay minutes carriers reported here, and the remaining four split what is left.
- 50%Carrier
- 27%Late-arriving aircraft
- 14%Extreme weather
- 9%National Airspace System
Extreme weather accounts for 14% 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 2.3 times the usual weather exposure. The split is drawn from 4,204 reported delay minutes.
The largest share of delay minutes, 50%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 2,106 of the 4,204 delay minutes reported here.
Cancellations are rare at 0.43%, below the national 1.89% 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 costs
Badly late arrivals are rare here: only 3.2% 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 is a different operation and performs like one: it runs 84.9% on time across 467 flights, 6 points below 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.
One caution: this is a thin sample. 467 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.
What to do with this
Booking Delta on MSO to SLC
Put together: treat all of this as provisional. 467 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 90.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 464 completed flights over 12 months sit behind that.
Related
Where to go next
- MSO to SLC, every carrier
- Delta on SLC to MSO, the return leg
- SkyWest Airlines on MSO to SLC91.8%
- Delta Air Lines network-wide record
- Salt Lake City International (SLC) delay statistics
- Worst months to fly in the US, ranked by the data
- Late aircraft, weather, or the airline: what actually causes US flight delays
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.