Flight number record
UA 516
United Airlines · Atlanta to Chicago
- Route
- ATL → ORD
- Departs
- 15:30
- Flights
- 364
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s UA 516, check with United Airlines.
UA 516 sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 5 points worse than the national rate of 77.6%. The late ones land close to two hours behind schedule. That rests on 364 flights, with a median arrival 3 minutes early.
The national on-time rate over the same period is 77.6%, so UA 516 runs 5 points behind the country as a whole. Across a thousand flights that is about 47 extra late arrivals.
Key figures
On time
72.9%
Arrivals under 15 minutes late, of 354 completed flights
Avg delay
122 min
Across delayed arrivals only, not all flights
Cancelled
1.65%
National rate is 1.81%
1 hour+ late
13.6%
National rate is 8.1%
These figures cover 364 flights between July 2025 and June 2026. Beyond the headline rate, 13.6% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Schedule
When UA 516 flies
UA 516 flies ATL to ORD without a single fixed slot. Its most common scheduled departure was 15:30, used on 90 of 364 flights, with 15:40 (73 flights) and 15:37 (48 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 15:3090 flights24.7%
- Departs 15:4073 flights20.1%
- Departs 15:3748 flights13.2%
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 15:30 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and UA 516 runs level with that at 72.9%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
Against the route
UA 516 next to ATL to ORD
Every carrier on ATL to ORD combined arrived on time 70.6% of the time across 6,406 flights, so UA 516 is 2 points ahead of it. United flew 1,611 flights on the same city pair under all its flight numbers, including this one, and those ran 74.3% on time. Across its whole network United Airlines managed 79.0%, which this flight trails by 6 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 516thin sample | 364 | 72.9% | 122 min | 1.65% | C |
| All United Airlines on ATL–ORD | 1,611 | 74.3% | 92 min | 1.55% | C |
| All carriers on ATL–ORD | 6,406 | 70.6% | 81 min | 2.34% | C |
| United Airlines, whole network | 821,041 | 79.0% | 72 min | 1.01% | B |
Across the year
UA 516 quarter by quarter
UA 516 did not run the same all year. Its best quarter was Jan–Mar 2026 at 77.3% on time and its weakest Apr–Jun 2026 at 66.3%, a swing of 11 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 flights75.9%
- Oct–Dec 202591 flights72.2%
- Jan–Mar 202690 flights77.3%
- Apr–Jun 202691 flights66.3%
Scale runs 60% to 85%. Rows with fewer than 30 flights show a dash.
By weekday, UA 516 did best on Saturday at 86.0% on time and worst on Monday at 66.7%. 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 UA 516 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 12,000 reported delay minutes.
- 40%National Airspace System
- 35%Late-arriving aircraft
- 23%Carrier
- 2%Extreme weather
35% 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 12,000 reported delay minutes here, that single category outweighs weather by 15 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 11,699 delay minutes reported on UA 516.
Cancellations sit at 1.65% against a national 1.81%, which is ordinary. Diversions add another 1.10%.
Connections and routes
What a delay on this flight costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 13.6% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 606 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.
The same number turns up on six other city pairs in the data, including ORD to BDL (113), ORD to SNA (58) and ORD to TVC (52), but none flew often enough under UA 516 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to ATL to ORD only.
One caution: this is a thin sample. 364 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 UA 516
For a booking, UA 516 is a flight to put a long connection behind. 13.6% of its completed flights arrived an hour or more late, which a short layover will not absorb. If the onward flight is on a separate ticket, the risk sits with you.
Related
Where to go next
- ATL to ORD, every carrier and departure
- ORD to ATL, the return direction
- Delta Air Lines 2738 on the same route60.6%
- Delta Air Lines 1147 on the same route79.2%
- Frontier Airlines 1441 on the same route70.8%
- United Airlines 1046 on the same route58.9%
- Delta Air Lines 2879 on the same route46.8%
- Delta Air Lines 1178 on the same route88.0%
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- Chicago O'Hare International (ORD) delay statistics
- United Airlines on-time record
- Every United Airlines 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 United Airlines’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.