ON TIMEBOARD

PDX → IAH on time

Portland (Portland, OR) to Houston Bush Intercontinental (Houston, TX). Every scheduled flight, September 2025 to August 2026.

On time
86%
arrived < 15 min late
Cancelled
0.5%
1,208 flights
Typical arrival
−11 min
median vs schedule
When late
+66 min
average delay
Flights / day
3
2 airlines

86% of flights from Portland to Houston arrived on time over the past 12 months. That is better than the typical U.S. route. The 7 a.m. departures ran on time 93% of the time; the 10 a.m. ones 77%. Most reliable airline: United Airlines (87%). 5% 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 PDX → IAH: when a flight was late, it was under 45 minutes late 59% of the time. About 1 in 26 flights landed an hour or more late, and 1 in 101 three hours or more; 0.5% were cancelled outright.

Share of all 1,208 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
United Airlines85587%0.4%−11 min4.6%+77 minUnited Airlines
Alaska Airlines35384%0.9%−9 min2.3%+43 minAlaska 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 PDX). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%7 a.m. departures: 93% on time (509 flights)937a8 a.m. departures: too few flights8a9 a.m. departures: too few flights9a10 a.m. departures: 77% on time (178 flights)7710a11 a.m. departures: too few flights (29 flights)11anoon departures: 87% on time (132 flights)8712p1 p.m. departures: 79% on time (179 flights)791p2 p.m. departures: too few flights (43 flights)2p3 p.m. departures: too few flights3p4 p.m. departures: too few flights4p5 p.m. departures: too few flights5p6 p.m. departures: too few flights6p7 p.m. departures: too few flights7p8 p.m. departures: too few flights8p9 p.m. departures: too few flights9p10 p.m. departures: too few flights (1 flights)10p11 p.m. departures: 81% on time (136 flights)8111p
PDX → IAH, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

By airline and hour

DepartsUnited AirlinesAlaska Airlines
7 a.m.93%94%
10 a.m.—77%
noon87%—
1 p.m.79%—
11 p.m.81%—

Last flight of the day

On PDX → IAH, each airline's last flight of the day was cancelled 0.0% of the time, against 0.6% for its earlier flights, so here the last flight is actually the safer one. It arrived 3+ hours late 1.1% of the time (earlier flights: 1.2%). 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.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
United Airlines11:59 p.m.0.0%1.1%0.6%first flight 7:13 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: September (93%). Worst: July (74%).

40%70%100%Jan: 82% on time (221 flights)82JanFeb: 91% on time (194 flights)91FebMar: 87% on time (215 flights)87MarApr: 91% on time (211 flights)91AprMay: 82% on time (277 flights)82MayJun: 80% on time (325 flights)80JunJul: 74% on time (333 flights)74JulAug: 87% on time (294 flights)87AugSep: 93% on time (245 flights)93SepOct: 88% on time (268 flights)88OctNov: 87% on time (212 flights)87NovDec: 87% on time (239 flights)87Dec

By day of week

DayFlightsOn timeCancelled
Monday18087%0.0%
Tuesday16289%0.0%
Wednesday17285%0.6%
Thursday17785%0.0%
Friday17781%0.6%
Saturday16288%0.6%
Sunday17887%1.7%

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Airline (crew, maintenance, ops) 39%Late inbound plane 32%Air traffic & airport (NAS) 28%Security 1%

Cancellations: weather 5 · airline 1

Month by month

60%80%100%Sep 2023Jan 2024Jan 2025Jan 2026Jun 2025: 73% on time, 2.5% cancelledJul 2025: 75% on time, 2.4% cancelledAug 2025: 79% on time, 0.9% cancelledOct 2025: 81% on time, 0.9% cancelledDec 2025: 89% on time, 0.0% cancelledMay 2026: 86% on time, 0.0% cancelledJun 2026: 84% on time, 0.0% cancelledJul 2026: 74% on time, 0.9% cancelled
Share of flights on time, by month (hover a point for cancellations)
PDX → IAH, monthly on-time and cancellation rate.

Flight numbers on this route

Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.

FlightDepartsFlightsOn timeCancelledTypical arrivalOperated by
UA 4627:00 a.m.25391%1.2%−13 minUnited Airlines
AS 14207:05 a.m.34884%0.9%−9 minAlaska Airlines
UA 19271:02 p.m.14679%0.0%−9 minUnited Airlines

Worst days in the past year

DateFlightsOn timeCancelled
Mar 16, 202630%0
Nov 20, 202530%0
Mar 11, 202630%1
Mar 8, 202630%1
Jun 20, 2026425%0

Questions

How often are flights from PDX to IAH on time?

86% of 1,208 scheduled flights from Portland, OR to Houston, TX arrived within 15 minutes of schedule between September 2025 and August 2026. 0.5% were cancelled.

What is the best time of day to fly PDX to IAH?

Flights scheduled to leave at 7 a.m. were the most reliable (93% on time). The 10 a.m. departures were the least (77%).

Which airline is most on time from PDX to IAH?

United Airlines: 87% of its 855 flights on the route arrived on time. Alaska Airlines: 84%.

What month has the most delays from PDX to IAH?

July (74% on time). The best month is September (93%), over 2023–2026.

Is the last flight of the day from PDX to IAH more likely to be cancelled?

No, the opposite. Each airline's last PDX–IAH flight of the day was cancelled 0.0% of the time over the past year, against 0.6% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

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.