Washington (IAD) to Miami (MIA): On-Time Performance
Data through May 2026
Washington (IAD) to Miami (MIA) effectively runs on two schedules. In October 2024, 97% of arrivals were on time; in July 2025 that fell to 64% — a 33-point seasonal swing. Across the full period the route averages 82% on-time against a national 78%. Morning departures also hold up better than evening ones (87% vs 68%), which matters most in the rough months.
- On-time
- 82%
- arrived <15 min late
- Avg delay
- 15 min
- completed flights
- Cancelled
- 0.9%
- Flights/day
- 1.8
- last 12 months
- Duration
- 2h 53m
- scheduled
- Distance
- 922 mi
Best airline from IAD to MIA
2 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 85% | 11 min | 0.7% | 1,020 |
| Frontier Airlines | 62% | 38 min | 2.4% | 166 |
Monthly on-time trend
Best time to fly from IAD to MIA
Aim for departures around 9 a.m. (89% on-time); avoid 9 p.m. departures (50%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 81% | 24 min |
| Tuesday | 84% | 12 min |
| Wednesdaybest | 86% | 5 min |
| Thursday | 78% | 17 min |
| Friday | 82% | 12 min |
| Saturday | 86% | 13 min |
| Sunday | 76% | 16 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft45%
- Airline operations18%
- National airspace system35%
- Weather2%
Frequently asked questions
- How often are flights from IAD to MIA delayed?
- 18% of IAD–MIA flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 15 minutes.
- Which airline is most reliable from IAD to MIA?
- United Airlines has the best on-time record on this route at 85%, based on 1,020 flights. 2 airlines flew IAD–MIA frequently enough to compare in this period.
- What is the best time of day to fly from IAD to MIA?
- Departures around 9 a.m. have the best record (89% on-time), while departures around 9 p.m. have the worst (50%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from IAD to MIA?
- The scheduled IAD–MIA flight time averages 2h 53m over 922 miles. Actual arrival times vary — flights on this route land 15+ minutes late 18% of the time.
- How often are IAD to MIA flights cancelled?
- 0.9% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from IAD to MIA?
- July 2025 was the roughest month in this dataset, with only 64% of arrivals on time. The best was October 2024 at 97%. If your dates are flexible, that 33-point gap is worth planning around.
Explore related pages
More routes from IAD
Other ways to fly to Miami (MIA)
Related guides
Based on 1,186 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.