Carrier route record
UAIAH→PDX
United Airlines · Houston to Portland
- Flights
- 856
- Period
- September 2025 to August 2026
- Share of route
- 71%
- Carriers
- 2
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on IAH to PDX lands a B+, 5 points better than the national rate of 77.3%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That rests on 856 flights, with a median arrival 8 minutes early.
Set against the rest of the country, United's IAH to PDX record is 5 points better than the US average of 77.3%. That gap is worth roughly 50 fewer late arrivals for every thousand flights.
Key figures
On time
82.3%
Arrivals under 15 minutes late, of 851 completed flights
Avg delay
62 min
Across delayed arrivals only, not all flights
Cancelled
0.23%
National rate is 1.89%
Whole route
80.9%
Every carrier on IAH to PDX, 1,209 flights
These figures cover 856 flights between September 2025 and August 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.
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Carrier by carrier
United against every carrier on IAH to PDX
United flew 856 of the 1,209 flights on IAH to PDX, most of the route. Its 82.3% on time is about level with the route as a whole at 80.9%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from United at 82.3% to Alaska at 77.6%. 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) | 856 | 82.3% | 62 min | 0.23% | B+ |
| Alaska Airlinesthin sample | 353 | 77.6% | 61 min | 1.13% | B |
Flight by flight
United flight numbers on IAH to PDX
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When United runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 856 flights.
- 5am–8am—
- 8am–11am365 flights86.8%
- 11am–2pm—
- 2pm–5pm131 flights83.8%
- 5pm–8pm20 flights—
- 8pm–5am340 flights77.2%
Scale runs 70% to 90%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 86.8% of the time, against 77.2% for the overnight window. That is 10 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 365 flights scheduled in it.
Across the year
United on IAH to PDX through the year
June is the worst month at 73.8% on time, 18 points below April, the best at 91.7%. 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. May was the busiest month here, with 88 flights.
Across the week, Sunday is the strongest day at 86.3% on time and Friday the weakest at 80.2%, a spread of 6 points.
Arrival by arrival
How late United on IAH to PDX runs when it is late
United on IAH to PDX often beats the schedule: 285 of 851 completed flights, 33%, arrived 15 minutes or more early. The 151 late arrivals split 48 under half an hour, 50 between 30 and 60 minutes, and 53 an hour or more.
- 15+ min early285 flights33.5%
- Within 15 min415 flights48.8%
- 15–29 min late48 flights5.6%
- 30–59 min late50 flights5.9%
- 1–2 hours late36 flights4.2%
- 2+ hours late17 flights2.0%
Scale runs 0% to 100%.
Share of 851 completed flights by arrival against schedule.
A late pushback is often recovered here: of 185 departures that left 15 minutes late or more, 56 still arrived on time. 22 flights left on time and still arrived late.
The worst days
Worst days for United on IAH to PDX
The latest arrival of the period was on 24 November 2025, 5 hours 47 minutes behind schedule; most of its delay minutes were filed as extreme weather. The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 24 November 2025 | 5 hours 47 minutes | Extreme weather |
| 30 April 2026 | 5 hours 15 minutes | Late-arriving aircraft |
| 16 June 2026 | 5 hours 4 minutes | Carrier |
| 25 October 2025 | 4 hours 46 minutes | Extreme weather |
| 19 May 2026 | 3 hours 26 minutes | Extreme weather |
Delay causes
Why United runs late on this route
Late-arriving aircraft accounts for 47% of the 9,385 delay minutes carriers reported here, and the remaining four split what is left.
- 47%Late-arriving aircraft
- 30%Carrier
- 12%National Airspace System
- 11%Extreme weather
Extreme weather accounts for 11% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 1.9 times the usual weather exposure. The split is drawn from 9,385 reported delay minutes.
47% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 9,385 reported delay minutes here, that single category outweighs weather by 4 to one.
Cancellations are rare at 0.23%, below the national 1.89% 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 8.3%, so 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.
At 1,825 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg is a different operation and performs like one: it runs 87.1% on time across 855 flights, 5 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 5 points of difference.
One caution: this is a thin sample. 856 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking United on IAH to PDX
Put together: treat all of this as provisional. 856 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 82.3% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 851 completed flights over 12 months sit behind that.
Related
Where to go next
- IAH to PDX, every carrier
- United on PDX to IAH, the return leg
- Alaska Airlines on IAH to PDX77.6%
- United Airlines network-wide record
- George Bush Intercontinental (IAH) delay statistics
- Portland International (PDX) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.