Carrier route record
UAIAH→FLL
United Airlines · Houston to Fort Lauderdale
- Flights
- 1,792
- Period
- July 2025 to June 2026
- Share of route
- 65%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on IAH to FLL earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 1,792 flights, with a median arrival 10 minutes early.
Set against the rest of the country, United's IAH to FLL record is 7 points better than the US average of 77.6%. That gap is worth roughly 74 fewer late arrivals for every thousand flights.
Key figures
On time
85.0%
Arrivals under 15 minutes late, of 1,776 completed flights
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
0.73%
National rate is 1.81%
Whole route
79.8%
Every carrier on IAH to FLL, 2,760 flights
These figures cover 1,792 flights between July 2025 and June 2026. The median arrival is 10 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 IAH to FLL
United flew 1,792 of the 2,760 flights on IAH to FLL, most of the route. Its 85.0% on time is 5 points better than the route as a whole, which runs 79.8%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from United at 85.0% to Frontier at 59.0%. 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) | 1,792 | 85.0% | 64 min | 0.73% | A+ |
| Spirit Airlines | 864 | 71.6% | 73 min | 1.85% | C |
| Frontier Airlinesthin sample | 104 | 59.0% | 48 min | 3.85% | D− |
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 16 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–8am220 flights94.5%
- 8am–11am447 flights84.0%
- 11am–2pm238 flights88.7%
- 2pm–5pm497 flights84.6%
- 5pm–8pm390 flights78.8%
- 8pm–5am—
Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 94.5% of the time, against 78.8% for the evening window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 497 flights scheduled in it.
Across the year
United on IAH to FLL through the year
June is the worst month at 70.6% on time, 25 points below January, the best at 95.3%. 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. December was the busiest month here, with 184 flights.
Across the week, Tuesday is the strongest day at 90.7% on time and Sunday the weakest at 81.7%. 9 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 17,000 reported delay minutes.
- 35%Late-arriving aircraft
- 31%Carrier
- 27%National Airspace System
- 6%Extreme weather
35% 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 17,000 reported delay minutes here, that single category outweighs weather by 6 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 17,008 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 94.5% on time here.
Cancellations are rare at 0.73%, 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
5.3% 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 966 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 is a different operation and performs like one: it runs 88.3% on time across 1,792 flights, 3 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 3 points of difference.
The sample behind these figures is 1,792 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 IAH to FLL
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 95.3% on time and June 70.6%, a swing of 25 points. If the dates move at all, move them out of June before you think about anything else. 1,776 completed flights over 12 months sit behind that.
Related
Where to go next
- IAH to FLL, every carrier
- United on FLL to IAH, the return leg
- Spirit Airlines on IAH to FLL71.6%
- Frontier Airlines on IAH to FLL59.0%
- United Airlines network-wide record
- George Bush Intercontinental (IAH) delay statistics
- Fort Lauderdale-Hollywood International (FLL) 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.