Carrier performance at one airport
DL→PDX
Delta Air Lines at Portland International
- Departures
- 7,151
- Period
- September 2025 to August 2026
- Routes
- 7
- Rank here
- #1 of 7
Delta Air Lines at Portland earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 13 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 7,151 flights, of which Delta Air Lines flew 7,151 at 90.1% on time.
Measured against the airport rather than the country, Delta Air Lines runs 7 points ahead of the 82.8% weighted average across all carriers at PDX. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
90.1%
7,055 completed departures
Avg delay
74 min
Across delayed flights only
Cancelled
1.08%
At PDX, this carrier only
Rank here
#1
Of 7 carriers clearing the floor at PDX
These figures cover 7,151 flights between September 2025 and August 2026. The median arrival is 12 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.
Against the competition
Every carrier at PDX, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 90.1% of the time; Southwest Airlines manages 75.7%. Sample sizes sit next to every figure, because a two-point gap across 8,585 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines (this page) | 7,151 | 90.1% | 74 min | 1.08% | A |
| SkyWest Airlines | 10,587 | 85.3% | 64 min | 0.55% | A+ |
| Alaska Airlines | 24,677 | 83.0% | 46 min | 0.66% | B+ |
| American Airlines | 4,484 | 81.3% | 111 min | 1.83% | B |
| United Airlines | 6,624 | 80.6% | 65 min | 0.59% | B+ |
| Frontier Airlines | 799 | 79.6% | 78 min | 1.25% | B |
| Southwest Airlines | 8,585 | 75.7% | 48 min | 0.33% | B+ |
The spread between Delta and Southwest is 14 points, wide enough that it should decide the booking. On a hundred trips that is 14 more arrivals inside the on-time window.
Route by route
Where Delta Air Lines flies from PDX
Delta Air Lines operates 7 routes out of PDX with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| PDX to SLC · Salt Lake City | 1,696 | 90.8% | 61 min | 1.47% | A |
| PDX to LAX · Los Angeles | 1,688 | 90.4% | 91 min | 0.83% | A+ |
| PDX to MSP · Minneapolis | 1,332 | 91.4% | 64 min | 0.68% | A+ |
| PDX to ATL · Atlanta | 1,257 | 90.2% | 60 min | 0.95% | A+ |
| PDX to JFK · New York | 550 | 91.0% | 72 min | 2.36% | A |
| PDX to DTW · Detroit | 377 | 79.6% | 104 min | 1.06% | B |
| PDX to SEA · Seattlethin sample | 250 | 89.6% | 68 min | 0.00% | A+ |
Flight by flight
Delta Air Lines flight numbers from PDX
7 Delta Air Lines flight numbers leaving PDX flew their main route often enough to have a record of their own. Grouped by destination.
Departure window
Best time of day for this operation
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 7,151 flights.
- 5am–8am2,039 flights94.6%
- 8am–11am566 flights91.3%
- 11am–2pm1,872 flights87.0%
- 2pm–5pm500 flights88.7%
- 5pm–8pm990 flights88.5%
- 8pm–5am1,184 flights88.6%
Scale runs 80% to 100%.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 87.0% on time against 94.6% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 5am–8am window is the busiest, with 2,039 flights scheduled in it.
Across the year
Seasonal pattern
July is the worst month at 85.7% on time, 9 points below March, the best at 94.2%. 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 676 flights.
Delay causes
What holds this operation up
- 45%Carrier
- 45%Late-arriving aircraft
- 10%National Airspace System
- 0%Extreme weather
45% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 52,000 reported delay minutes here, that single category outweighs weather by 45 to one. The split is drawn from 51,674 reported delay minutes.
Cancellations sit at 1.08% against a national 1.89%, which is ordinary. Diversions add another 0.27%.
Badly late arrivals are rare here: only 3.0% land an hour or more behind schedule, against 8.3% 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.
The sample behind these figures is 7,151 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.
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 14 points, which is the most any booking decision can do. 7,055 completed flights over 12 months sit behind that.
Common questions
Delta Air Lines at PDX
How often is Delta Air Lines at PDX delayed?
About one flight in ten arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 9.9% of the 7,151 flights in this analysis, against 22.7% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on Delta Air Lines at PDX?
Delta Air Lines leads at 90.1% on time across 7,151 flights. Southwest Airlines is at the other end on 75.7%, a gap of 14 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 Delta Air Lines at PDX?
The 5am–8am departure window is the strongest at 94.6% on time. The 11am–2pm window is the weakest at 87.0%, 8 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 Delta Air Lines at PDX?
July is the weakest month at 85.7% on time, compared with 94.2% in March. Across the year that is 9 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
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.