Route reliability record
SLC→HLN
Salt Lake City to Helena
- Flights
- 725
- Period
- July 2025 to June 2026
- Distance
- 402 mi
- Carriers
- 1
This route earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 19 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 35 minutes. That rests on 725 SLC to HLN flights, with a median arrival 15 minutes early.
Set against the rest of the country, this route's record is 19 points better than the US average of 77.6%. That gap is worth roughly 188 fewer late arrivals for every thousand flights.
Key figures
On time
96.4%
Arrivals under 15 minutes late, of 723 completed flights
Avg delay
36 min
Across delayed arrivals only, not all flights
Cancelled
0.28%
National rate is 1.81%
Best carrier
SkyWest
96.4% on time across 725 flights
These figures cover 725 flights between July 2025 and June 2026. The median arrival is 15 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 SLC to HLN
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 | 725 | 96.4% | 36 min | 0.28% | A+ |
Flight by flight
Flights on SLC to HLN
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.
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 725 flights.
- 5am–8am—
- 8am–11am360 flights95.8%
- 11am–2pm—
- 2pm–5pm—
- 5pm–8pm—
- 8pm–5am365 flights97.0%
Scale runs 85% to 100%. Rows with fewer than 30 flights show a dash.
The overnight block holds up unusually well at 97.0% on time across 365 flights. Red-eyes fly into empty airspace and empty gates, and they are the first rotation of the aircraft's day rather than the last. The 8pm–5am window is the busiest, with 365 flights scheduled in it.
Across the year
When delays peak on this route
Twelve months, one bar each, drawn from the same 725 flights. The strip shows how much of this route's record is set by the calendar rather than by the operation.
February is the weak month at 92.9% on time, against 100.0% in December. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. March was the busiest month here, with 62 flights.
The day of the week is close to irrelevant here: 2 points separates the best day from the worst. Weekly demand peaks are not what drives the delays on this operation.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Carrier accounts for 76% of the 940 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.
- 76%Carrier
- 16%Extreme weather
- 8%National Airspace System
Extreme weather accounts for 16% 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 2.5 times the usual weather exposure. The split is drawn from 940 reported delay minutes.
The largest share of delay minutes, 76%, 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 716 of the 940 delay minutes reported here.
Cancellations are rare at 0.28%, 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 0.6% 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.
At 402 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 8pm–5am window matters as much as it does.
The return leg runs 95.9% on time across 725 flights, within half a point 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. 725 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 HLN after this flight
What to do with this
Booking this route
Put together: treat all of this as provisional. 725 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 96.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 723 completed flights over 12 months sit behind that.
Common questions
SLC to HLN questions
How often is SLC to HLN delayed?
About one flight in 30 arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 3.6% of the 725 flights in this analysis, against 22.4% nationally. Delayed flights are late by roughly 35 minutes on average.
How reliable is SLC to HLN compared with the rest of the country?
96.4% of flights arrive on time here against a national 77.6%, a difference of 19 points in its favour. That is worth a A+ on this site's grading scale.
What time of day has the fewest delays on SLC to HLN?
The 8pm–5am departure window is the strongest at 97.0% on time. The 8am–11am window is the weakest at 95.8%, about a point 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 February delays on SLC to HLN?
February is the weakest month at 92.9% on time, compared with 100.0% in December. Across the year that is 7 points between the best and worst months. The seasonal swing is modest enough that it should not decide when you travel.
Related
Where to go next
- HLN to SLC — the return legseparate record
- Salt Lake City International (SLC) delay statistics
- SLC to DEN, a related route77.8%
- DEN to HLN, a related route78.9%
- SLC to PHX, a related route83.9%
- SkyWest Airlines on-time record96.4%
- Late aircraft, weather, or the airline: what actually causes US flight delays
- How to read this site: grades, sample sizes, and honest caveats
Direction matters. SLC to HLN and HLN to SLC are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed SLC to HLN’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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.