Route reliability record
TUL→DEN
Tulsa to Denver
- Flights
- 2,474
- Period
- September 2025 to August 2026
- Distance
- 541 mi
- Carriers
- 4
This route lands a B, 3 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That rests on 2,474 TUL to DEN flights, of which Southwest Airlines flew 894 at 82.8% on time.
Best time to fly TUL to DEN: a 5am–8am departure, ideally on a Friday. Flights in that window arrived on time 94.1% of the time and Friday flights 82.6%, against 80.4% for the route overall.
Southwest Airlines is the most reliable of the three carriers covered here at 82.8% on time across 894 flights.
Key figures
On time
80.4%
Arrivals under 15 minutes late, of 2,444 completed flights
Avg delay
68 min
Across delayed arrivals only, not all flights
Cancelled
1.05%
National rate is 1.89%
Best carrier
Southwest
82.8% on time across 894 flights
These figures cover 2,474 flights between September 2025 and August 2026. The median arrival is 5 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
Which airline is most reliable on TUL to DEN
The three carriers here are closely matched: 6 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 |
|---|---|---|---|---|---|
| Southwest Airlines | 894 | 82.8% | 63 min | 1.01% | B |
| SkyWest Airlines | 1,173 | 79.9% | 82 min | 0.94% | B+ |
| United Airlines | 365 | 76.9% | 41 min | 1.64% | B |
| Frontier Airlinesthin sample | 42 | 73.8% | 64 min | 0.00% | C+ |
No carrier stands out. Southwest tops the table at 82.8%, 6 points clear of the bottom, which is inside the range this kind of sample moves year to year.
Flight by flight
Flights on TUL 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.
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Best ways to make this trip
The most reliable ways to fly Tulsa to Denver
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. TUL → DENTulsa to Denver | Southwest Airlines | 82.0% | 82.8% | 1.01% | 5am–8am, Tue | — |
| 2. TUL → DENTulsa to Denver | SkyWest Airlines | 79.1% | 79.9% | 0.94% | 5am–8am, Sat | OO 5667 06:00 |
| 3. TUL → DENTulsa to Denver | United Airlines | 75.6% | 76.9% | 1.64% | 8am–11am, Mon | — |
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 matters more here than the choice of carrier. The gap between the best and worst window is 29 points, against 6 points between the best and worst carrier.
- 5am–8am650 flights94.1%
- 8am–11am490 flights79.9%
- 11am–2pm484 flights83.6%
- 2pm–5pm25 flights—
- 5pm–8pm713 flights65.5%
- 8pm–5am112 flights81.2%
Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 94.1% of the time, against 65.5% for the evening window. That is 29 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 713 flights scheduled in it.
Explore
Filter TUL to DEN 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 TUL to DEN, the best departure window is 5am–8am at 94.1% on time and the worst is 5pm–8pm at 65.5%, a wide gap of 28.6 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am94.1%
- 8–11am79.9%
- 11am–2pm83.6%
- 2–5pm—
- 5–8pm65.5%
- 8pm–5am81.2%
best all US flightsScale 55% to 100%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 19 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.
August is the worst month at 70.9% on time, 19 points below January, the best at 89.8%. 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. July was the busiest month here, with 236 flights.
Across the week, Friday is the strongest day at 82.6% on time and Wednesday the weakest at 77.5%, a spread of 5 points.
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 33,000 reported delay minutes.
- 34%National Airspace System
- 30%Carrier
- 24%Late-arriving aircraft
- 12%Extreme weather
Extreme weather accounts for 12% 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 2.0 times the usual weather exposure. The split is drawn from 32,679 reported delay minutes.
34% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 11,000 minutes out of 33,000, against a national NAS share of 21%.
Cancellations sit at 1.05% against a national 1.89%, which is ordinary. Diversions add another 0.16%.
Connections and stage length
What a delay here actually costs
7.1% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
The 541 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.
The return leg runs 77.6% on time across 2,475 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.
The sample behind these figures is 2,474 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. January runs 89.8% on time and August 70.9%, a swing of 19 points. If the dates move at all, move them out of August before you think about anything else. 2,444 completed flights over 12 months sit behind that.
Common questions
TUL to DEN questions
How often is TUL to DEN delayed?
About one flight in five arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 19.6% of the 2,474 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 TUL to DEN?
Southwest Airlines leads at 82.8% on time across 894 flights. United Airlines is at the other end on 76.9%, a gap of 6 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 TUL to DEN?
The 5am–8am departure window is the strongest at 94.1% on time. The 5pm–8pm window is the weakest at 65.5%, 29 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 August delays on TUL to DEN?
August is the weakest month at 70.9% on time, compared with 89.8% in January. Across the year that is 19 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
- DEN to TUL — the return legseparate record
- Denver International (DEN) delay statistics
- Southwest Airlines on TUL to DEN82.8%
- SkyWest Airlines on TUL to DEN79.9%
- United Airlines on TUL to DEN76.9%
- TUL to DFW, a related route79.1%
- PHX to DEN, a related route76.7%
- TUL to ORD, a related route78.1%
- Southwest Airlines on-time record82.8%
- SkyWest Airlines on-time record79.9%
- United Airlines on-time record76.9%
- The best time of day to fly, according to 7.05 million flight records
- Worst months to fly in the US, ranked by the data
Direction matters. TUL to DEN and DEN to TUL are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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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.