Route reliability record
DEN→RAP
Denver to Rapid City
- Flights
- 2,887
- Period
- July 2025 to June 2026
- Distance
- 301 mi
- Carriers
- 2
This route lands a B, level with the national rate of 77.6%. Roughly one flight in five arrive 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 2,887 flights, of which SkyWest Airlines flew 2,125 at 78.6% on time.
The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
77.9%
Arrivals under 15 minutes late, of 2,845 completed flights
Avg delay
68 min
Across delayed arrivals only, not all flights
Cancelled
1.14%
National rate is 1.81%
Best carrier
SkyWest
78.6% on time across 2,125 flights
These figures cover 2,887 flights between July 2025 and June 2026. Beyond the headline rate, 8.1% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Which airline is most reliable on DEN to RAP
The two carriers here are closely matched: 2 points 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 | 2,125 | 78.6% | 70 min | 1.41% | B |
| United Airlines | 762 | 76.2% | 64 min | 0.39% | B+ |
No carrier stands out. SkyWest tops the table at 78.6%, 2 points clear of the bottom, which is inside the range this kind of sample moves year to year.
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 19 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am119 flights89.8%
- 8am–11am459 flights83.7%
- 11am–2pm608 flights82.3%
- 2pm–5pm622 flights76.0%
- 5pm–8pm718 flights70.9%
- 8pm–5am361 flights76.5%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 89.8% of the time, against 70.9% for the evening window. That is 19 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 718 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 24 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.
July is the worst month at 66.8% on time, 24 points below November, the best at 90.7%. 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. August was the busiest month here, with 276 flights.
Across the week, Tuesday is the strongest day at 82.7% on time and Saturday the weakest at 74.0%. 9 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 43,000 reported delay minutes.
- 40%Late-arriving aircraft
- 37%Carrier
- 16%National Airspace System
- 7%Extreme weather
40% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 43,000 reported delay minutes here, that single category outweighs weather by 6 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 42,784 reported delay minutes.
The largest share of delay minutes, 37%, 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 16,000 of the 43,000 delay minutes reported here.
Cancellations sit at 1.14% against a national 1.81%, which is ordinary. Diversions add another 0.31%.
Connections and stage length
What a delay here actually costs
8.1% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route are the a little over an hour kind, which a normal layover absorbs.
At 301 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 79.0% on time across 2,887 flights, within about a point 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 2,887 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.
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 90.7% on time and July 66.8%, a swing of 24 points. If the dates move at all, move them out of July before you think about anything else. 2,845 completed flights over 12 months sit behind that.
Common questions
DEN to RAP questions
How often is DEN to RAP delayed?
Roughly one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 22.1% of the 2,887 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on DEN to RAP?
SkyWest Airlines leads at 78.6% on time across 2,125 flights. United Airlines is at the other end on 76.2%, a gap of 2 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 DEN to RAP?
The 5am–8am departure window is the strongest at 89.8% on time. The 5pm–8pm window is the weakest at 70.9%, 19 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 DEN to RAP?
July is the weakest month at 66.8% on time, compared with 90.7% in November. Across the year that is 24 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
- RAP to DEN — the return legseparate record
- Denver International (DEN) delay statistics
- SkyWest Airlines on-time record78.6%
- United Airlines on-time record76.2%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. DEN to RAP and RAP to DEN are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.