Portland, OR · departure reliability

PDX

Portland International

Departures: 62,458
Period: June 2025 to May 2026
Carriers: 9
US rank: #32 by volume

Terminal building and aircraft stands at a US airport

Portland

Portland International lands a B+, 5 points better than the national rate of 77.4%. About one flight in six arrive 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 62,458 flights, of which Delta Air Lines flew 7,318 at 89.4% on time.

Delta Air Lines is the most reliable of the nine carriers covered here at 89.4% on time across 7,318 flights.

On time

82.4%

Departures arriving under 15 minutes late at their destination

Avg delay

60 min

Across delayed flights only

Cancelled

0.77%

National rate is 1.80%

Best carrier

Delta

89.4% on time here

These figures cover 62,000 flights between June 2025 and May 2026. The median arrival is 6 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

Which airlines run best out of PDX

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 89.4% of the time; Hawaiian Airlines manages 57.7%. Sample sizes sit next to every figure, because a two-point gap across 540 flights means less than a ten-point one.

On-time performance by carrier departing PDX
Airline	Flights	On time	Avg delay	Cancelled	Grade
Alaska Airlines	22,840	82.8%	47 min	0.74%	B+
SkyWest Airlines	10,452	84.7%	63 min	0.57%	B+
Southwest Airlines	8,633	77.1%	48 min	0.32%	B+
Delta Air Lines	7,318	89.4%	77 min	0.98%	A+
United Airlines	6,521	82.3%	65 min	0.67%	B+
American Airlines	4,386	79.7%	98 min	1.92%	B
Frontier Airlines	1,008	76.1%	74 min	1.79%	B
Hawaiian Airlines	540	57.7%	74 min	0.93%	D+
Allegiant Air	436	72.1%	119 min	0.00%	C+

The spread between Delta and Hawaiian is 32 points, wide enough that it should decide the booking. On a hundred trips that is 32 more arrivals inside the on-time window.

Route by route

Busiest routes out of PDX

Route-level records vary far more than the airport average. These are the 25 busiest departures from PDX, each with its own on-time rate against the airport-wide 82.4%.

Busiest routes from PDX by flight volume
Route	Flights	On time	Avg delay	Cancelled	Grade
PDX to SEA · Seattle	4,937	84.1%	55 min	0.67%	B+
PDX to LAX · Los Angeles	4,447	86.8%	77 min	0.99%	A+
PDX to DEN · Denver	4,298	80.0%	54 min	0.49%	B+
PDX to PHX · Phoenix	3,745	80.1%	69 min	0.56%	B+
PDX to SFO · San Francisco	3,530	75.0%	58 min	0.42%	B+
PDX to LAS · Las Vegas	3,025	80.8%	53 min	0.46%	B+
PDX to ORD · Chicago	2,733	77.3%	70 min	0.95%	B+
PDX to DFW · Dallas-Fort Worth	2,441	80.1%	88 min	2.29%	B
PDX to SLC · Salt Lake City	2,398	88.3%	60 min	0.79%	A+
PDX to SMF · Sacramento	1,996	82.7%	53 min	0.30%	B+
PDX to SAN · San Diego	1,787	80.0%	42 min	0.67%	B+
PDX to SJC · San Jose	1,611	81.5%	53 min	0.12%	B+
PDX to ATL · Atlanta	1,593	87.4%	55 min	0.94%	A+
PDX to SNA · Santa Ana	1,543	89.9%	35 min	1.43%	A
PDX to MSP · Minneapolis	1,488	91.4%	62 min	0.47%	A+
PDX to OAK · Oakland	1,272	76.8%	51 min	0.71%	B+
PDX to IAH · Houston	1,238	84.6%	64 min	0.89%	B+
PDX to ANC · Anchorage	1,148	79.7%	46 min	0.00%	B+
PDX to BUR · Burbank	984	85.0%	50 min	0.91%	A+
PDX to GEG · Spokane	930	85.1%	42 min	0.97%	A+
PDX to BOI · Boise	919	86.8%	47 min	0.76%	A+
PDX to HNL · Honolulu	917	61.1%	66 min	1.20%	D
PDX to JFK · New York	914	84.3%	60 min	2.19%	B
PDX to EWR · Newark	824	81.7%	76 min	2.06%	B
PDX to PSP · Palm Springs	738	83.7%	49 min	1.36%	B

Departure window

The best time of day to leave PDX

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 62,000 flights.

5am–8am15,287 flights87.7%
8am–11am11,056 flights83.3%
11am–2pm8,565 flights80.3%
2pm–5pm9,790 flights80.2%
5pm–8pm9,699 flights78.0%
8pm–5am8,061 flights81.5%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 87.7% of the time, against 78.0% for the evening 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.

Across the year

When PDX runs late

Twelve months, one bar each, drawn from the same 62,458 flights. The strip shows how much of PDX's record is set by the calendar rather than by the operation.

Darker means more delays. Figures are on-time percentages.February best, July worst

July is the worst month at 75.7% on time, 11 points below February, the best at 86.3%. 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.

Across the week, Saturday is the strongest day at 84.8% on time and Thursday the weakest at 80.3%. 5 points is a smaller lever than departure hour, but it is free.

Delay causes

Why PDX gets delayed

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 649,000 reported delay minutes.

Carrier
37%
Late-arriving aircraft
37%
National Airspace System
24%
Extreme weather
2%
Security
0%

37% 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 649,000 reported delay minutes here, that single category outweighs weather by 15 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 largest share of delay minutes, 37%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 240,000 of the 649,000 delay minutes reported here.

Cancellations are rare at 0.77%, below the national 1.80% 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.

Badly late arrivals are rare here: only 4.5% land an hour or more behind schedule, against 8.2% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

62,458 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.

What to do with this

Flying out of PDX

Put together: take the 5am–8am departure, avoid July if the dates are flexible, and if two carriers are within a few dollars of each other, Delta is the one with the record behind it. None of that guarantees an on-time arrival; it moves the odds by 32 points, which is the most any booking decision can do.

Common questions

PDX delay questions

How often is Portland (PDX) delayed?

About one flight in six arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 17.6% of the 62,458 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.

Which airline is most reliable on Portland (PDX)?

Delta Air Lines leads at 89.4% on time across 7,318 flights. Hawaiian Airlines is at the other end on 57.7%, a gap of 32 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.

What time of day has the fewest delays on Portland (PDX)?

The 5am–8am departure window is the strongest at 87.7% on time. The 5pm–8pm window is the weakest at 78.0%, 10 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.

How bad are July delays on Portland (PDX)?

July is the weakest month at 75.7% on time, compared with 86.3% in February. Across the year that is 11 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.

Key figures