Atlanta to Denver Flight Delays
Sample size: 17,583 ATL–DEN flights, January 2023 to December 2025 (BTS). 24.13% of Atlanta to Denver flights arrived at least 15 minutes late. That tracks the 24.2% median for the major US domestic routes DelayGuard covers almost exactly. Departure time moves the odds more than anything else on this route: 06:00 departures run 9.04% late against 41.92% for 19:00. Tuesday is the calmest day at 21.14%, Sunday the worst at 26.93%. Cancellations (2024 to 2025) peak in July at 3.25% of scheduled flights and bottom out in February at 0%. Last updated: 2026-10-01.
These figures are historical US domestic rates, not a forecast for one departure. Use the flight delay prediction before you book.
ATL airport delay guide · DEN airport delay guide · Predict a ATL to DEN flight
Best time to fly ATL to DEN
The best time to fly ATL to DEN is the 6 AM departure and fly on a Tuesday, not a Sunday (21.14% against 26.93%): 9.04% of 6 AM flights arrived 15+ minutes late, against 41.92% at 7 PM.
Lowest observed delay rates depart 06:00–08:00. The highest sit at 18:00–19:00, 22:00. Only departure hours with at least 100 recorded flights are listed, so sparse hours are blank rather than estimated.
| Departure hour | Delayed 15+ min | Flights observed |
|---|---|---|
| 06:00 | 9.04% | 907 |
| 07:00 | 14.46% | 1,279 |
| 08:00 | 12.48% | 1,578 |
| 09:00 | 20.45% | 1,056 |
| 10:00 | 15.38% | 676 |
| 11:00 | 15.28% | 1,780 |
| 12:00 | 19.36% | 780 |
| 13:00 | 20.3% | 1,350 |
| 14:00 | 25.04% | 635 |
| 15:00 | 26.93% | 791 |
| 16:00 | 32.04% | 1,670 |
| 17:00 | 30.34% | 534 |
| 18:00 | 35.34% | 1,146 |
| 19:00 | 41.92% | 780 |
| 20:00 | 34.04% | 564 |
| 21:00 | 33.89% | 1,012 |
| 22:00 | 40.99% | 949 |
ATL to DEN flight time and distance
Scheduled gate-to-gate time from ATL to DEN is a median 3 h 21 min. Flights actually took a median 3 h 15 min gate to gate, including 2 h 49 min in the air. 3.3% ran 30 or more minutes over schedule and 68.7% arrived sooner than scheduled (BTS data, January 2023 to December 2025).
ATL to DEN is 1,199 miles (BTS data).
| Airline | Scheduled (median) | Actual (median) | In the air (median) | 30+ min over schedule | Flights |
|---|---|---|---|---|---|
| Delta Air Lines | 3 h 18 min | 3 h 13 min | 2 h 48 min | 3.6% | 8,448 |
| Southwest Airlines | 3 h 20 min | 3 h 11 min | 2 h 51 min | 2.2% | 4,007 |
| United Airlines | 3 h 27 min | 3 h 19 min | 2 h 50 min | 3.5% | 3,168 |
| Frontier Airlines | 3 h 29 min | 3 h 22 min | 2 h 49 min | 4.2% | 1,959 |
How late, and why
When a ATL to DEN flight was late (15+ minutes), it arrived an average of 62 minutes late (median 39). 7.8% of all completed flights arrived an hour or more late (BTS data, 2023 to 2025).
Of the delay minutes on late ATL to DEN flights, 35.5% were caused by the airline (crew, maintenance, ground handling), 34.8% by a late incoming aircraft, 25.8% by the air-traffic system (volume, non-extreme weather, airport operations), 3.9% by extreme weather and 0.2% by security (BTS data, 2023 to 2025).
| Cause | Share of delay minutes |
|---|---|
| airline | 35.5% |
| late incoming aircraft | 34.8% |
| air-traffic system | 25.8% |
| extreme weather | 3.9% |
| security | 0.2% |
BTS assigns causes to delay minutes on flights that arrived 15+ minutes late. "Air-traffic system" includes non-extreme weather that slows traffic.
ATL to DEN delays by day of week
| Day | Delayed 15+ min | Flights observed |
|---|---|---|
| Mon | 24.07% | 2,638 |
| Tue | 21.14% | 2,483 |
| Wed | 21.2% | 2,472 |
| Thu | 26.13% | 2,591 |
| Fri | 25.3% | 2,589 |
| Sat | 23.91% | 2,263 |
| Sun | 26.93% | 2,547 |
Month-by-month cancellation pattern
Share of scheduled ATL–DEN flights cancelled in each month, from BTS 2024–2025 on-time reporting. These are cancellations, not delays. Delay figures on this page cover January 2023 to December 2025.
| Month | Cancelled | Flights scheduled |
|---|---|---|
| Jan | 3.19% | 910 |
| Feb | 0% | 843 |
| Mar | 0.84% | 955 |
| Apr | 0.2% | 983 |
| May | 0.29% | 1,039 |
| Jun | 0.76% | 1,050 |
| Jul | 3.25% | 1,078 |
| Aug | 0.59% | 1,013 |
| Sep | 0.32% | 944 |
| Oct | 0.1% | 974 |
| Nov | 0.66% | 914 |
| Dec | 0.85% | 945 |
Airlines on ATL to DEN: delays and cancellations
Delta Air Lines, Southwest Airlines, United Airlines and Frontier Airlines fly this route today. Only carriers with at least 200 scheduled flights on the pairing are listed. Delay rates cover January 2023 to December 2025; cancellation rates cover 2024 to 2025.
| Airline | Share of flights | Delayed 15+ min | Cancelled | Flights scheduled |
|---|---|---|---|---|
| Delta Air Lines | 48% | 23.04% | 0.83% | 5,642 |
| Southwest Airlines | 22% | 23.88% | 0.77% | 2,584 |
| United Airlines | 18% | 17.9% | 1.22% | 2,133 |
| Frontier Airlines | 11% | 39.46% | 1.24% | 1,289 |
Related pages
- ATL delays: rate, worst hours and live risk
- DEN delays: rate, worst hours and live risk
- US airline cancellation rates
- Thanksgiving and Christmas 2026 flight delay guide
- Predict a ATL to DEN flight
Check your odds: Will my flight be delayed? · Will my flight be cancelled?
ATL vs DEN: airport conditions
Both ends of a route shape its delay profile. These are DelayGuard's operational scores for Atlanta and Denver.
| Measure | ATL (Atlanta) | DEN (Denver) |
|---|---|---|
| Congestion | high | high |
| Weather risk | moderate | moderate |
| NAS vulnerability | high | moderate |
| Average taxi-out | 18 min | 17 min |
| Runways | 5 | 6 |
ATL to DEN questions
- How long is the flight from Atlanta to Denver?
- Scheduled gate-to-gate time from ATL to DEN is a median 3 h 21 min, and flights actually took a median 3 h 15 min including 2 h 49 min in the air. 3.3% ran 30+ minutes over schedule (BTS data, January 2023 to December 2025).
- How often do ATL to DEN flights get delayed?
- Across 17,583 recorded ATL–DEN departures, January 2023 to December 2025 (BTS), 24.13% arrived at least 15 minutes late. Departure time matters most: 6:00 departures run 9.04% late against 41.92% for 19:00. Actual delay frequency varies by airline, time of day, and season.
- What is the best time of year to fly ATL to DEN?
- Atlanta (GA) sees its highest delays during June–September (convective/thunderstorm season). Denver (CO) peaks during December–February (winter weather) and June–August (summer storms). The dominant seasonal risk on this route sits at the destination (Denver) — use the DelayGuard predictor to check conditions for your specific travel date.
- Which airline is most reliable on ATL to DEN?
- On ATL→DEN, United Airlines has the lowest measured delay rate at 17.9% of 3,168 flights, and Frontier Airlines the highest at 39.46% (BTS, January 2023 to December 2025). Southwest Airlines cancels the fewest at 0.77% (2024 to 2025). These are route-specific figures, not airline-wide averages.
- How late are ATL to DEN flights when they are delayed?
- When a ATL to DEN flight was late (15+ minutes), it arrived an average of 62 minutes late (median 39). 7.8% of all completed flights arrived an hour or more late (BTS data, 2023 to 2025).
- How accurate is DelayGuard's delay prediction for this route?
- DelayGuard's delay risk score comes from an ML model trained on BTS data (3.95 million US domestic flights, 2023 to mid-2025), with live weather data (within 5 days of departure) and FAA NAS advisories (within 6 hours) — a likelihood of delay, not a guarantee.
Delay figures reflect arrivals 15 or more minutes late in BTS on-time reporting. Cancellation figures are separate and count flights that never operated. Hours, days and months with fewer than 100 recorded flights are omitted rather than estimated.