Carrier route record
UAIAD→TPA
United Airlines · Washington to Tampa
- Flights
- 1,180
- Period
- July 2025 to June 2026
- Share of route
- 86%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on IAD to TPA lands a B+, 5 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 1,180 flights, with a median arrival 8 minutes early.
Set against the rest of the country, United's IAD to TPA record is 5 points better than the US average of 77.6%. That gap is worth roughly 46 fewer late arrivals for every thousand flights.
Key figures
On time
82.2%
Arrivals under 15 minutes late, of 1,173 completed flights
Avg delay
67 min
Across delayed arrivals only, not all flights
Cancelled
0.42%
National rate is 1.81%
Whole route
81.2%
Every carrier on IAD to TPA, 1,366 flights
These figures cover 1,180 flights between July 2025 and June 2026. The median arrival is 8 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.
Carrier by carrier
United against every carrier on IAD to TPA
United flew 1,180 of the 1,366 flights on IAD to TPA, most of the route. Its 82.2% on time is about level with the route as a whole at 81.2%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from United at 82.2% to Frontier at 74.9%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines (this page) | 1,180 | 82.2% | 67 min | 0.42% | B+ |
| Frontier Airlinesthin sample | 186 | 74.9% | 77 min | 3.76% | C− |
Flight by flight
United flight numbers on IAD to TPA
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 20 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am366 flights90.7%
- 11am–2pm352 flights87.1%
- 2pm–5pm26 flights—
- 5pm–8pm348 flights70.6%
- 8pm–5am88 flights78.2%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 90.7% of the time, against 70.6% for the evening window. That is 20 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 366 flights scheduled in it.
Across the year
United on IAD to TPA through the year
July is the worst month at 67.1% on time, 26 points below April, the best at 93.3%. 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 149 flights.
Across the week, Tuesday is the strongest day at 87.5% on time and Sunday the weakest at 78.0%. 10 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
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 14,000 reported delay minutes.
- 40%Late-arriving aircraft
- 31%National Airspace System
- 18%Carrier
- 10%Extreme weather
40% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 14,000 reported delay minutes here, that single category outweighs weather by 4 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 13,950 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 90.7% on time here.
Cancellations are rare at 0.42%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
6.2% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
The 811 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 84.2% on time across 1,182 flights, within 2 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 1,180 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.
What to do with this
Booking United on IAD to TPA
Put together: the calendar is the biggest lever here, not the carrier or the hour. April runs 93.3% on time and July 67.1%, a swing of 26 points. If the dates move at all, move them out of July before you think about anything else. 1,173 completed flights over 12 months sit behind that.
Related
Where to go next
- IAD to TPA, every carrier
- United on TPA to IAD, the return leg
- Frontier Airlines on IAD to TPA74.9%
- United Airlines network-wide record
- Washington Dulles International (IAD) delay statistics
- Tampa International (TPA) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.