Flight number record
DL 539
Delta Air Lines · Atlanta to Portland
- Route
- ATL → PDX
- Departs
- 08:25
- Flights
- 365
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s DL 539, check with Delta Air Lines.
DL 539 earns a B. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 35 minutes. That rests on 365 flights, with a median arrival 4 minutes early.
Set against the rest of the country, DL 539's record is 7 points better than the US average of 77.6%. That gap is worth roughly 65 fewer late arrivals for every thousand flights.
Key figures
On time
84.1%
Arrivals under 15 minutes late, of 358 completed flights
Avg delay
37 min
Across delayed arrivals only, not all flights
Cancelled
1.64%
National rate is 1.81%
1 hour+ late
1.7%
National rate is 8.1%
These figures cover 365 flights between July 2025 and June 2026. The median arrival is 4 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 539 flies
DL 539 flies ATL to PDX without a single fixed slot. Its most common scheduled departure was 08:25, used on 73 of 365 flights, with 08:20 (60 flights) and 08:10 (59 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 08:2573 flights20.0%
- Departs 08:2060 flights16.4%
- Departs 08:1059 flights16.2%
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 08:25 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and DL 539 runs level with that at 84.1%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
Against the route
DL 539 next to ATL to PDX
Every carrier on ATL to PDX combined arrived on time 79.6% of the time across 1,576 flights, so DL 539 is 5 points ahead of it. Delta flew 1,288 flights on the same city pair under all its flight numbers, including this one, and those ran 79.0% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 3 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 539 | 365 | 84.1% | 37 min | 1.64% | B |
| All Delta Air Lines on ATL–PDX | 1,288 | 79.0% | 49 min | 1.01% | B |
| All carriers on ATL–PDX | 1,576 | 79.6% | 53 min | 0.89% | B+ |
| Delta Air Lines, whole network | 1,038,570 | 81.6% | 71 min | 1.62% | B |
Across the year
DL 539 quarter by quarter
DL 539 did not run the same all year. Its best quarter was Jul–Sep 2025 at 93.5% on time and its weakest Oct–Dec 2025 at 74.4%, a swing of 19 points on roughly 91 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 flights93.5%
- Oct–Dec 202592 flights74.4%
- Jan–Mar 202690 flights75.6%
- Apr–Jun 202691 flights92.2%
Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.
By weekday, DL 539 did best on Thursday at 94.2% on time and worst on Wednesday at 75.0%. Each day rests on about 52 flights, so a gap of 19 points is worth noticing but could still narrow in another year.
Delay causes
Why DL 539 runs late
One category carries most of the weight here. Carrier accounts for 48% of the 2,133 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.
- 48%Carrier
- 44%National Airspace System
- 5%Extreme weather
- 3%Late-arriving aircraft
The largest share of delay minutes, 48%, 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 1,020 of the 2,133 delay minutes reported here. The split is drawn from 2,133 delay minutes reported on DL 539.
Cancellations sit at 1.64% against a national 1.81%, which is ordinary. Diversions add another 0.27%.
Connections and routes
What a delay on this flight costs
Badly late arrivals are rare here: only 1.7% land an hour or more behind schedule, against 8.1% 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.
At 2,172 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
DL 539 is not only a ATL to PDX flight. It also flew PDX to ATL (303 flights, 86.2% 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. 365 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 ATLthin sample | 303 | 86.2% | 57 min | 0.99% | A+ |
What to do with this
Booking DL 539
For a booking, read DL 539 as 84.1% on time with 1.64% cancelled over 365 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- ATL to PDX, every carrier and departure
- PDX to ATL, the return direction
- Delta Air Lines 503 on the same route74.3%
- Delta Air Lines 478 on the same route73.6%
- Alaska Airlines 783 on the same route81.8%
- Hartsfield-Jackson Atlanta International (ATL) 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.