Flight number record
DL 829
Delta Air Lines · Salt Lake City to Los Angeles
- Route
- SLC → LAX
- Departs
- 11:20
- Flights
- 365
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s DL 829, check with Delta Air Lines.
DL 829 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 about 55 minutes. That rests on 365 flights, with a median arrival 7 minutes early.
Set against the rest of the country, DL 829's record is 10 points better than the US average of 77.6%. That gap is worth roughly 100 fewer late arrivals for every thousand flights.
Key figures
On time
87.6%
Arrivals under 15 minutes late, of 363 completed flights
Avg delay
55 min
Across delayed arrivals only, not all flights
Cancelled
0.55%
National rate is 1.81%
1 hour+ late
2.5%
National rate is 8.1%
These figures cover 365 flights between July 2025 and June 2026. The median arrival is 7 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 829 flies
DL 829 flies SLC to LAX without a single fixed slot. Its most common scheduled departure was 11:20, used on 120 of 365 flights, with 11:15 (61 flights) and 11:30 (55 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 11:20120 flights32.9%
- Departs 11:1561 flights16.7%
- Departs 11:3055 flights15.1%
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 11:20 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.8%, and DL 829 runs 9 points better at 87.6%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
Against the route
DL 829 next to SLC to LAX
Every carrier on SLC to LAX combined arrived on time 86.2% of the time across 4,146 flights, so DL 829 is about level with it. Delta flew 2,454 flights on the same city pair under all its flight numbers, including this one, and those ran 85.4% 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 829 | 365 | 87.6% | 55 min | 0.55% | A+ |
| All Delta Air Lines on SLC–LAX | 2,454 | 85.4% | 51 min | 0.41% | A+ |
| All carriers on SLC–LAX | 4,146 | 86.2% | 55 min | 0.46% | A+ |
| Delta Air Lines, whole network | 1,038,570 | 81.6% | 71 min | 1.62% | B |
Across the year
DL 829 quarter by quarter
DL 829 did not run the same all year. Its best quarter was Oct–Dec 2025 at 93.4% on time and its weakest Jan–Mar 2026 at 75.3%, a swing of 18 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 flights91.3%
- Oct–Dec 202592 flights93.4%
- Jan–Mar 202690 flights75.3%
- Apr–Jun 202691 flights90.1%
Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.
By weekday, DL 829 ranged from 80.8% on Saturday to 92.3% on Wednesday. With about 52 flights behind each day, a spread of 12 points is inside normal variation, so the day you fly is not worth changing for this flight.
Delay causes
Why DL 829 runs late
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 2,453 reported delay minutes.
- 38%Carrier
- 36%Late-arriving aircraft
- 18%Extreme weather
- 9%National Airspace System
Extreme weather accounts for 18% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the quarterly figures above are the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.8 times the usual weather exposure. The split is drawn from 2,453 delay minutes reported on DL 829.
Cancellations are rare at 0.55%, 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
Badly late arrivals are rare here: only 2.5% 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.
The 590 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.
Every one of the 365 flights under DL 829 in the data flew SLC to LAX. The number was not reused on any other city pair, which makes this a clean record of one route.
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.
What to do with this
Booking DL 829
For a booking, DL 829 has one of the better records a US domestic flight can show: 87.6% on time and 0.55% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- SLC to LAX, every carrier and departure
- LAX to SLC, the return direction
- Delta Air Lines 841 on the same route79.5%
- Delta Air Lines 1087 on the same route93.3%
- Delta Air Lines 1142 on the same route78.6%
- Delta Air Lines 1095 on the same route90.8%
- Delta Air Lines 1161 on the same route83.7%
- Frontier Airlines 1267 on the same route88.4%
- Salt Lake City International (SLC) delay statistics
- Los Angeles International (LAX) 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
- Why the first flight of the morning is statistically safest
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.