77% of flights from Denver to Atlanta arrived on time over the past 12 months. That is about the typical U.S. route. The 5 a.m. departures ran on time 94% of the time; the 7 p.m. ones 39%. Most reliable airline: Delta Air Lines (84%). 7% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for DEN → ATL: when a flight was late, it was under 45 minutes late 59% of the time. About 1 in 17 flights landed an hour or more late, and 1 in 112 three hours or more; 0.9% were cancelled outright.
- On time or early77%
- 15–30 min late8.1%
- 30–60 min late7.1%
- 1–2 hours late3.7%
- 2–3 hours late1.2%
- 3+ hours late0.9%
- Diverted0.5%
- Cancelled0.9%
Share of all 5,603 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| Delta Air Lines | 2,807 | 84% | 1.2% | −11 min | 4.0% | +61 min | Delta Air Lines |
| Southwest Airlines | 1,072 | 62% | 0.8% | +6 min | 9.4% | +51 min | Southwest Airlines |
| United Airlines | 923 | 77% | 0.3% | −6 min | 6.8% | +61 min | United Airlines |
| Frontier Airlines | 801 | 75% | 0.9% | −5 min | 6.7% | +62 min | Frontier Airlines |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at DEN). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | Delta Air Lines | Southwest Airlines | United Airlines | Frontier Airlines |
|---|---|---|---|---|
| 12 a.m. | 91% | — | — | 90% |
| 5 a.m. | 95% | — | — | — |
| 6 a.m. | 92% | — | — | 84% |
| 7 a.m. | 92% | — | — | — |
| 9 a.m. | 81% | — | — | — |
| 10 a.m. | 81% | 75% | 81% | — |
| 11 a.m. | 77% | — | — | — |
| noon | 86% | — | — | — |
| 1 p.m. | 79% | — | 77% | 81% |
| 2 p.m. | 83% | 55% | — | — |
| 3 p.m. | 83% | — | — | — |
| 4 p.m. | 79% | — | — | — |
| 5 p.m. | — | — | 71% | — |
| 7 p.m. | — | 39% | — | — |
| 11 p.m. | — | — | — | 61% |
Last flight of the day
On DEN → ATL, each airline's last flight of the day was cancelled 1.1% of the time, against 0.9% for its earlier flights (1.3× as often). It arrived 3+ hours late 2.0% of the time (earlier flights: 0.5%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| Delta Air Lines | 4:35 p.m. | 1.6% | 1.9% | 1.1% | first flight 12:56 a.m. |
| Frontier Airlines | 11:50 p.m. | 1.8% | 1.5% | 0.2% | first flight 6:30 a.m. |
| United Airlines | 5:48 p.m. | 0.3% | 1.9% | 0.4% | first flight 10:00 a.m. |
| Southwest Airlines | 7:05 p.m. | 0.8% | 2.5% | 0.9% | first flight 10:45 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
If you need to be in ATL tonight, book an earlier flight so there's a backup if it's cancelled.
By month
Each calendar month pooled over 2023–2026. Best: November (85%). Worst: July (65%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 840 | 78% | 0.6% |
| Tuesday | 813 | 81% | 0.5% |
| Wednesday | 785 | 81% | 0.4% |
| Thursday | 793 | 76% | 0.3% |
| Friday | 827 | 76% | 1.1% |
| Saturday | 748 | 77% | 2.3% |
| Sunday | 797 | 74% | 1.5% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: airline 28 · weather 18 · air traffic/airport 6
Month by month
Flight numbers on this route
Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| DL 302 | 12:55 a.m. | 177 | 90% | 1.1% | −18 min | Delta Air Lines |
| DL 341 | 6:00 a.m. | 365 | 93% | 0.8% | −12 min | Delta Air Lines |
| F9 3294 | 6:30 a.m. | 290 | 87% | 0.0% | −12 min | Frontier Airlines |
| DL 431 | 7:05 a.m. | 365 | 92% | 1.6% | −12 min | Delta Air Lines |
| DL 2235 | 9:39 a.m. | 263 | 84% | 0.8% | −7 min | Delta Air Lines |
| F9 3600 | 9:58 a.m. | 331 | 70% | 0.3% | −3 min | Frontier Airlines |
| UA 2424 | 10:00 a.m. | 236 | 82% | 0.4% | −7 min | United Airlines |
| DL 346 | 10:50 a.m. | 339 | 77% | 1.5% | −4 min | Delta Air Lines |
| UA 1671 | 1:26 p.m. | 195 | 77% | 0.5% | −7 min | United Airlines |
| DL 957 | 3:15 p.m. | 214 | 83% | 0.5% | −13 min | Delta Air Lines |
| DL 840 | 4:43 p.m. | 317 | 79% | 1.9% | −14 min | Delta Air Lines |
| UA 1305 | 5:48 p.m. | 360 | 71% | 0.3% | −4 min | United Airlines |
| F9 1450 | 11:59 p.m. | 179 | 62% | 2.8% | +5 min | Frontier Airlines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Mar 7, 2026 | 15 | 13% | 3 |
| Mar 6, 2026 | 15 | 20% | 3 |
| Dec 3, 2025 | 14 | 29% | 0 |
| Jul 19, 2026 | 17 | 29% | 2 |
| Apr 17, 2026 | 15 | 33% | 0 |
Questions
How often are flights from DEN to ATL on time?
77% of 5,603 scheduled flights from Denver, CO to Atlanta, GA arrived within 15 minutes of schedule between September 2025 and August 2026. 0.9% were cancelled.
What is the best time of day to fly DEN to ATL?
Flights scheduled to leave at 5 a.m. were the most reliable (94% on time). The 7 p.m. departures were the least (39%).
Which airline is most on time from DEN to ATL?
Delta Air Lines: 84% of its 2,807 flights on the route arrived on time. Southwest Airlines: 62%. United Airlines: 77%. Frontier Airlines: 75%.
What month has the most delays from DEN to ATL?
July (65% on time). The best month is November (85%), over 2023–2026.
Is the last flight of the day from DEN to ATL more likely to be cancelled?
Yes. Each airline's last DEN–ATL flight of the day was cancelled 1.1% of the time over the past year, against 0.9% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- ATL → DEN (return)
- Denver (DEN) delays by hour
- Flights into Atlanta Hartsfield-Jackson (ATL)
- Delta Air Lines on-time record
- Southwest Airlines on-time record
- United Airlines on-time record
- Frontier Airlines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.