Airport month record

PDXDEC

Portland International in December 2025

Departures: 5,124
Month: December 2025
National, same month: 73.2%
Carriers: 8

Historical statistics for December 2025, not live status or a forecast for this year’s December. For today’s conditions at PDX, see live FAA status.

PDX in December lands a B+, 6 points better than the national rate of 73.2%. About one flight in five arrives 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 5,124 flights, of which Delta Air Lines flew 576 at 85.9% on time.

Delta Air Lines is the most reliable of the five carriers covered here at 85.9% on time across 576 flights.

On time

79.3%

Arrivals under 15 minutes late, of 5,080 completed departures

Avg delay

59 min

Across delayed arrivals only, not all flights

Cancelled

0.60%

Nationally in December: 1.55%

Whole year

82.6%

PDX across all twelve months

These figures cover 5,124 departures from Portland International in December 2025. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.

Against the year

December next to PDX's other months

Against PDX's own year, December ran 3 points worse than the twelve-month rate of 82.6%, which makes it number eleven of twelve months, best first. Either side of it, November ran 84.2% on time and January 85.6%, so a trip moved by a few weeks would have landed in a better stretch.

PDX month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	5,864	75.7%	65 min	1.18%	B
August 2025	5,685	80.9%	60 min	0.67%	B+
September 2025	5,269	83.7%	51 min	0.17%	B+
October 2025	5,493	82.1%	53 min	0.64%	B+
November 2025	4,976	84.2%	59 min	1.51%	B
December 2025 (this page)	5,124	79.3%	59 min	0.60%	B+
January 2026	4,537	85.6%	66 min	1.41%	A
February 2026	4,182	86.3%	56 min	0.69%	A+
March 2026	5,113	86.3%	69 min	0.94%	A+
April 2026	5,040	86.1%	63 min	0.48%	A+
May 2026	5,535	83.9%	62 min	0.42%	B+
June 2026	6,024	80.3%	65 min	0.61%	B+

Departure window

The best time of day to leave PDX in December

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 5,124 flights.

5am–8am1,331 flights84.4%
8am–11am931 flights80.7%
11am–2pm551 flights76.4%
2pm–5pm772 flights78.1%
5pm–8pm815 flights74.6%
8pm–5am724 flights76.5%

Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 84.4% of the time, against 74.6% 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. The 5am–8am window is the busiest, with 1,331 flights scheduled in it.

Across the week, Thursday is the strongest day at 82.2% on time and Friday the weakest at 73.9%. 8 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at PDX in December

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 85.9% of the time; Southwest Airlines manages 74.1%. Sample sizes sit next to every figure, because a two-point gap across 671 flights means less than a ten-point one.

Carriers at PDX in December 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
Alaska Airlines	2,075	77.2%	44 min	0.63%	B+
SkyWest Airlines	823	79.7%	69 min	0.73%	B+
Southwest Airlines	671	74.1%	47 min	0.15%	C+
Delta Air Lines	576	85.9%	55 min	1.04%	A
United Airlines	475	83.8%	75 min	0.00%	B+
American Airlinesthin sample	342	86.4%	107 min	0.88%	A+
Hawaiian Airlinesthin sample	75	65.8%	163 min	2.67%	C
Frontier Airlinesthin sample	59	71.2%	132 min	0.00%	C+

Delta leads Southwest by 12 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Route by route

Busiest routes out of PDX in December

Routes from PDX in December 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
PDX to SEA · Seattle	412	80.2%	58 min	0.49%	B+
PDX to LAX · Los Angeles	380	80.2%	53 min	0.26%	B+
PDX to DEN · Denverthin sample	346	76.5%	55 min	0.29%	B+
PDX to PHX · Phoenixthin sample	344	80.0%	68 min	0.87%	B+
PDX to LAS · Las Vegasthin sample	239	73.2%	64 min	0.00%	C+
PDX to SFO · San Franciscothin sample	238	73.4%	62 min	0.42%	C+
PDX to DFW · Dallas-Fort Worththin sample	212	86.3%	85 min	0.00%	A+
PDX to SLC · Salt Lake Citythin sample	201	86.4%	65 min	1.00%	A
PDX to SJC · San Josethin sample	184	81.0%	54 min	0.00%	B+
PDX to ORD · Chicagothin sample	164	78.4%	63 min	0.61%	B+
PDX to SAN · San Diegothin sample	157	67.7%	43 min	1.27%	C
PDX to SNA · Santa Anathin sample	149	82.8%	34 min	2.68%	B
PDX to SMF · Sacramentothin sample	137	73.7%	53 min	0.00%	C+
PDX to ATL · Atlantathin sample	122	88.4%	53 min	0.82%	A+
PDX to OAK · Oaklandthin sample	121	78.5%	42 min	0.00%	B+
PDX to MSP · Minneapolisthin sample	120	78.2%	56 min	0.83%	B+
PDX to GEG · Spokanethin sample	113	81.1%	38 min	1.77%	B
PDX to IAH · Houstonthin sample	105	88.6%	99 min	0.00%	A+
PDX to BUR · Burbankthin sample	100	76.8%	54 min	0.00%	B+
PDX to ANC · Anchoragethin sample	92	60.4%	49 min	0.00%	D+
PDX to PSP · Palm Springsthin sample	78	81.8%	44 min	1.28%	B
PDX to BOI · Boisethin sample	75	81.3%	37 min	0.00%	B+
PDX to HNL · Honoluluthin sample	75	65.8%	163 min	2.67%	C
PDX to MIA · Miamithin sample	64	85.9%	72 min	0.00%	A+
PDX to EWR · Newarkthin sample	62	75.8%	57 min	0.00%	B+

Delay causes

What held PDX up in December

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 62,000 reported delay minutes.

Late-arriving aircraft
37%
Carrier
37%
National Airspace System
21%
Extreme weather
5%
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 62,000 reported delay minutes here, that single category outweighs weather by 8 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 61,705 reported delay minutes.

Cancellations are rare at 0.60%, below the national 1.55% 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.

5.5% of arrivals land an hour or more late, close to the national 10.0%. 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.

What to do with this

Flying from PDX in December

For a December trip through PDX: plan on this being one of the airport's harder months. The 5am–8am departures held up best at 84.4% on time, and with 5.5% of arrivals an hour or more late, a connection here deserves more slack than the same trip in February would.

Portland International (PDX), the whole year
PDX in July75.7%
PDX in August80.9%
PDX in September83.7%
PDX in October82.1%
PDX in November84.2%
PDX in January85.6%
PDX in February86.3%
PDX in March86.3%
PDX in April86.1%
PDX in May83.9%
PDX in June80.3%

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.

Key figures