Skip to content
DelayAtlas

Route reliability record

CIDDEN

Cedar Rapids to Denver

Flights
1,103
Period
July 2025 to June 2026
Distance
692 mi
Carriers
3
BGRADE

This route lands a B, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 1,103 CID to DEN flights, with a median arrival 5 minutes early.

Best time to fly CID to DEN: a 5am–8am departure, ideally on a Friday. Flights in that window arrived on time 95.0% of the time and Friday flights 80.0%, against 77.5% for the route overall.

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

77.5%

Arrivals under 15 minutes late, of 1,085 completed flights

Avg delay

91 min

Across delayed arrivals only, not all flights

Cancelled

1.27%

National rate is 1.81%

Best carrier

United

79.2% on time across 727 flights

These figures cover 1,103 flights between July 2025 and June 2026. Beyond the headline rate, 9.3% 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 CID to DEN

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.

On-time performance by carrier on CID to DEN
AirlineFlightsOn timeAvg delayCancelledGrade
United Airlines72779.2%95 min1.51%B
Frontier Airlinesthin sample16976.6%71 min1.18%B
SkyWest Airlinesthin sample20772.3%95 min0.48%C+

Flight by flight

Flights on CID to DEN

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 matters more here than the choice of carrier. The gap between the best and worst window is 28 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

  • 5am–8am40 flights95.0%
  • 8am–11am365 flights82.7%
  • 11am–2pm
  • 2pm–5pm413 flights77.0%
  • 5pm–8pm198 flights66.8%
  • 8pm–5am87 flights74.7%

Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 95.0% of the time, against 66.8% for the evening window. That is 28 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 413 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 31 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 month83J87F78M84A86M74J56J68A83S83O87N66D
Darker means more delays. Figures are on-time percentages.February best, July worst

July is the worst month at 55.9% on time, 31 points below February, the best at 87.3%. 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. June was the busiest month here, with 125 flights.

Across the week, Friday is the strongest day at 80.0% on time and Monday the weakest at 73.5%. 7 points is a smaller lever than departure hour, but it is free.

On-time rate by day of the week73.5Mon79.9Tue76.6Wed76.1Thu80.0Fri76.7Sat79.8Sun
Monday: 73.5 percent on time. Tuesday: 79.9 percent on time. Wednesday: 76.6 percent on time. Thursday: 76.1 percent on time. Friday: 80.0 percent on time. Saturday: 76.7 percent on time. Sunday: 79.8 percent on time

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 22,000 reported delay minutes.

  • Carrier
    36%
  • Late-arriving aircraft
    28%
  • National Airspace System
    25%
  • Extreme weather
    10%

The largest share of delay minutes, 36%, 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 8,076 of the 22,000 delay minutes reported here. The split is drawn from 22,206 reported delay minutes.

The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 95.0% on time here.

Cancellations sit at 1.27% against a national 1.81%, which is ordinary. Diversions add another 0.36%.

Connections and stage length

What a delay here actually costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.3% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.

The 692 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 79.2% on time across 1,104 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 1,103 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 DEN 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. February runs 87.3% on time and July 55.9%, a swing of 31 points. If the dates move at all, move them out of July before you think about anything else. 1,085 completed flights over 12 months sit behind that.

Common questions

CID to DEN questions

How often is CID to DEN delayed?

Roughly one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 22.5% of the 1,103 flights in this analysis, against 22.4% nationally. Delayed flights are late by an hour and a half on average.

How reliable is CID to DEN compared with the rest of the country?

77.5% of flights arrive on time here against a national 77.6%, a difference of half a point against it. That is worth a B on this site's grading scale.

What time of day has the fewest delays on CID to DEN?

The 5am–8am departure window is the strongest at 95.0% on time. The 5pm–8pm window is the weakest at 66.8%, 28 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 CID to DEN?

July is the weakest month at 55.9% on time, compared with 87.3% in February. Across the year that is 31 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. CID to DEN and DEN to CID are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

Embed CID to DEN’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.