80% of flights from Denver to Washington arrived on time over the past 12 months. That is about the typical U.S. route. The 7 a.m. departures ran on time 91% of the time; the 4 p.m. ones 66%. Most reliable airline: United Airlines (88%). 8% 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 → DCA: when a flight was late, it was under 45 minutes late 49% of the time. About 1 in 15 flights landed an hour or more late, and 1 in 96 three hours or more; 0.7% were cancelled outright.
- On time or early80%
- 15–30 min late6.1%
- 30–60 min late6.3%
- 1–2 hours late4.4%
- 2–3 hours late1.4%
- 3+ hours late1.0%
- Diverted0.4%
- Cancelled0.7%
Share of all 1,347 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 |
|---|---|---|---|---|---|---|---|
| Frontier Airlines | 983 | 77% | 0.8% | −10 min | 8.2% | +72 min | Frontier Airlines |
| United Airlines | 364 | 88% | 0.3% | −11 min | 3.0% | +59 min | United 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 | Frontier Airlines | United Airlines |
|---|---|---|
| 7 a.m. | 91% | — |
| 9 a.m. | — | 88% |
| 11 a.m. | 74% | — |
| 4 p.m. | 66% | — |
Last flight of the day
On DEN → DCA, each airline's last flight of the day was cancelled 0.3% of the time, against 1.1% for its earlier flights, so here the last flight is actually the safer one. It arrived 3+ hours late 1.9% of the time (earlier flights: 0.8%). 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 |
|---|---|---|---|---|---|
| Frontier Airlines | 4:28 p.m. | 0.3% | 1.9% | 1.1% | first flight 7:30 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.
By month
Each calendar month pooled over 2023–2026. Best: December (86%). Worst: July (71%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 211 | 79% | 0.5% |
| Tuesday | 157 | 81% | 0.0% |
| Wednesday | 157 | 80% | 0.0% |
| Thursday | 205 | 77% | 1.0% |
| Friday | 207 | 76% | 0.5% |
| Saturday | 202 | 88% | 1.0% |
| Sunday | 208 | 78% | 1.4% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: airline 5 · weather 4
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 |
|---|---|---|---|---|---|---|
| F9 686 | 7:35 a.m. | 313 | 92% | 0.6% | −17 min | Frontier Airlines |
| UA 789 | 9:35 a.m. | 256 | 90% | 0.4% | −13 min | United Airlines |
| F9 688 | 11:25 a.m. | 312 | 74% | 1.6% | −8 min | Frontier Airlines |
| F9 690 | 4:38 p.m. | 358 | 65% | 0.3% | −5 min | Frontier Airlines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Apr 16, 2026 | 4 | 0% | 0 |
| Mar 16, 2026 | 4 | 0% | 0 |
| Jan 25, 2026 | 4 | 0% | 3 |
| Jun 11, 2026 | 3 | 0% | 0 |
| Dec 3, 2025 | 3 | 0% | 0 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Denver or Washington. None has been clearly more reliable than DEN → DCA.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| DEN → DCA (this route) | 1,347 | 80% | 0.7% |
| DEN → IAD Denver to Washington Dulles | 3,385 | 81% | 0.6% |
| DEN → BWI Denver to Baltimore/Washington | 2,781 | 76% | 1.0% |
Questions
How often are flights from DEN to DCA on time?
80% of 1,347 scheduled flights from Denver, CO to Washington, DC arrived within 15 minutes of schedule between September 2025 and August 2026. 0.7% were cancelled.
What is the best time of day to fly DEN to DCA?
Flights scheduled to leave at 7 a.m. were the most reliable (91% on time). The 4 p.m. departures were the least (66%).
Which airline is most on time from DEN to DCA?
United Airlines: 88% of its 364 flights on the route arrived on time. Frontier Airlines: 77%.
What month has the most delays from DEN to DCA?
July (71% on time). The best month is December (86%), over 2023–2026.
Is the last flight of the day from DEN to DCA more likely to be cancelled?
No, the opposite. Each airline's last DEN–DCA flight of the day was cancelled 0.3% of the time over the past year, against 1.1% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- DCA → DEN (return)
- Denver (DEN) delays by hour
- Flights into Washington Reagan National (DCA)
- Frontier Airlines on-time record
- United 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.