Flight number record
DL 2551
Delta Air Lines · Los Angeles to Portland
- Route
- LAX → PDX
- Departs
- 14:00
- Flights
- 349
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2551, check with Delta Air Lines.
DL 2551 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 10 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 349 flights, with a median arrival 15 minutes early.
Set against the rest of the country, DL 2551's record is 10 points better than the US average of 77.6%. That gap is worth roughly 95 fewer late arrivals for every thousand flights.
Key figures
On time
87.1%
Arrivals under 15 minutes late, of 348 completed flights
Avg delay
76 min
Across delayed arrivals only, not all flights
Cancelled
0.29%
National rate is 1.81%
1 hour+ late
6.6%
National rate is 8.1%
These figures cover 349 flights between July 2025 and June 2026. The median arrival is 15 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.
Schedule
When DL 2551 flies
DL 2551 flies LAX to PDX without a single fixed slot. Its most common scheduled departure was 14:00, used on 69 of 349 flights, with 13:40 (41 flights) and 14:20 (36 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 14:0069 flights19.8%
- Departs 13:4041 flights11.7%
- Departs 14:2036 flights10.3%
Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 14:00 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and DL 2551 runs 15 points better at 87.1%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
Against the route
DL 2551 next to LAX to PDX
Every carrier on LAX to PDX combined arrived on time 86.4% of the time across 4,406 flights, so DL 2551 is about level with it. Delta flew 1,690 flights on the same city pair under all its flight numbers, including this one, and those ran 86.2% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 6 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 2551thin sample | 349 | 87.1% | 76 min | 0.29% | A+ |
| All Delta Air Lines on LAX–PDX | 1,690 | 86.2% | 74 min | 0.89% | A+ |
| All carriers on LAX–PDX | 4,406 | 86.4% | 68 min | 0.84% | A+ |
| Delta Air Lines, whole network | 1,038,570 | 81.6% | 71 min | 1.62% | B |
Across the year
DL 2551 quarter by quarter
DL 2551 did not run the same all year. Its best quarter was Jul–Sep 2025 at 90.2% on time and its weakest Jan–Mar 2026 at 80.2%, a swing of 10 points on roughly 87 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
- Jul–Sep 202592 flights90.2%
- Oct–Dec 202580 flights87.3%
- Jan–Mar 202686 flights80.2%
- Apr–Jun 202691 flights90.1%
Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.
By weekday, DL 2551 did best on Wednesday at 96.0% on time and worst on Sunday at 81.6%. Each day rests on about 50 flights, so a gap of 14 points is worth noticing but could still narrow in another year.
Delay causes
Why DL 2551 runs late
One category carries most of the weight here. Carrier accounts for 68% of the 3,424 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 68%Carrier
- 30%Late-arriving aircraft
- 2%National Airspace System
The largest share of delay minutes, 68%, 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 2,319 of the 3,424 delay minutes reported here. The split is drawn from 3,424 delay minutes reported on DL 2551.
Cancellations are rare at 0.29%, below the national 1.81% 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 routes
What a delay on this flight costs
6.6% of arrivals land an hour or more late, close to the national 8.1%. 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 a little over an hour, which a normal layover absorbs.
The 833 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
DL 2551 is not only a LAX to PDX flight. It also flew PDX to LAX (347 flights, 88.4% on time) often enough to be scored on its own. Airlines attach one number to several legs of an aircraft's day, and each leg keeps its own record here, so check which city pair is on your booking before reading a rate.
One caution: this is a thin sample. 349 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.
| Also flown as | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| PDX to LAXthin sample | 347 | 88.4% | 107 min | 0.29% | A+ |
What to do with this
Booking DL 2551
For a booking, DL 2551 has one of the better records a US domestic flight can show: 87.1% on time and 0.29% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- LAX to PDX, every carrier and departure
- PDX to LAX, the return direction
- Delta Air Lines 2975 on the same route89.0%
- Delta Air Lines 2766 on the same route88.6%
- Alaska Airlines 1315 on the same route90.0%
- Alaska Airlines 1397 on the same route87.9%
- Delta Air Lines 2457 on the same route80.5%
- Delta Air Lines 2459 on the same route85.3%
- Los Angeles International (LAX) delay statistics
- Portland International (PDX) delay statistics
- Delta Air Lines on-time record
- Every Delta Air Lines flight number with a record
- The most and least reliable flight numbers in the US
- Worst months to fly in the US, ranked by the data
A flight number here means Delta Air Lines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
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.