Flight number record
UA 1878
United Airlines · Austin to Chicago
- Route
- AUS → ORD
- Departs
- 07:00
- Flights
- 328
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s UA 1878, check with United Airlines.
UA 1878 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 12 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 328 flights, with a median arrival 7 minutes early.
Set against the rest of the country, UA 1878's record is 12 points better than the US average of 77.3%. That gap is worth roughly 118 fewer late arrivals for every thousand flights.
Key figures
On time
89.1%
Arrivals under 15 minutes late, of 320 completed flights
Avg delay
72 min
Across delayed arrivals only, not all flights
Cancelled
1.83%
National rate is 1.89%
1 hour+ late
3.1%
National rate is 8.3%
These figures cover 328 flights between September 2025 and August 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.
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Schedule
When UA 1878 flies
UA 1878 flies AUS to ORD without a single fixed slot. Its most common scheduled departure was 07:00, used on 152 of 328 flights, with 06:40 (76 flights) and 06:30 (54 flights) next.
- Departs 07:00152 flights46.3%
- Departs 06:4076 flights23.2%
- Departs 06:3054 flights16.5%
Scale runs 0% to 100%.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 07:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and UA 1878 runs level with that at 89.1%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
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Against the route
UA 1878 next to AUS to ORD
Every carrier on AUS to ORD combined arrived on time 72.4% of the time across 3,182 flights, so UA 1878 is 17 points ahead of it. United flew 1,549 flights on the same city pair under all its flight numbers, including this one, and those ran 74.1% on time. Across its whole network United Airlines managed 78.8%, which this flight beats by 10 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 1878thin sample | 328 | 89.1% | 72 min | 1.83% | A |
| All United Airlines on AUS–ORD | 1,549 | 74.1% | 83 min | 1.29% | C |
| All carriers on AUS–ORD | 3,182 | 72.4% | 93 min | 2.11% | C |
| United Airlines, whole network | 830,825 | 78.8% | 73 min | 1.02% | B |
Across the year
UA 1878 quarter by quarter
UA 1878 did not run the same all year. Its best quarter was Jul–Sep 2026 at 95.2% on time and its weakest Oct–Dec 2025 at 82.9%, a swing of 12 points on roughly 82 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 202529 flights—
- Oct–Dec 202577 flights82.9%
- Jan–Mar 202688 flights85.5%
- Apr–Jun 202672 flights90.0%
- Jul–Sep 202662 flights95.2%
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
By weekday, UA 1878 did best on Thursday at 96.2% on time and worst on Monday at 82.7%. Each day rests on about 47 flights, so a gap of 14 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late UA 1878 runs when it is late
UA 1878 often beats the schedule: 80 of 320 completed flights, 25%, arrived 15 minutes or more early. Most of the lateness is short. 18 of the 35 late arrivals were under half an hour behind, and 10 reached an hour or more.
- 15+ min early80 flights25.0%
- Within 15 min205 flights64.1%
- 15–29 min late18 flights5.6%
- 30–59 min late7 flights2.2%
- 1–2 hours late7 flights2.2%
- 2+ hours late3 flights0.9%
Scale runs 0% to 100%.
Share of 320 completed flights by arrival against schedule.
Only 16 of 320 completed flights left 15 minutes late or more, too few to say how often the time is made up.
The worst days
Worst days for UA 1878
The latest arrival of the period was on 20 April 2026, 9 hours 14 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). On three of the five worst days the largest share was filed as national airspace system delay.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 20 April 2026 | 9 hours 14 minutes | Carrier |
| 11 January 2026 | 7 hours 50 minutes | Carrier |
| 7 December 2025 | 3 hours 50 minutes | National Airspace System |
| 20 January 2026 | 1 hour 57 minutes | National Airspace System |
| 10 November 2025 | 1 hour 54 minutes | National Airspace System |
Delay causes
Why UA 1878 runs late
Carrier accounts for 51% of the 2,512 delay minutes carriers reported here, and the remaining four split what is left.
- 51%Carrier
- 43%National Airspace System
- 6%Late-arriving aircraft
The largest share of delay minutes, 51%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,274 of the 2,512 delay minutes reported here. The split is drawn from 2,512 delay minutes reported on UA 1878.
Cancellations sit at 1.83% against a national 1.89%, which is ordinary. Diversions add another 0.61%.
Connections and routes
What a delay on this flight costs
Badly late arrivals are rare here: only 3.1% land an hour or more behind schedule, against 8.3% 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 977 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.
The same number turns up on eight other city pairs in the data, including ORD to CLE (53), ORD to OMA (21) and ORD to EWR (20), but none flew often enough under UA 1878 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to AUS to ORD only.
One caution: this is a thin sample. 328 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 1878
For a booking, read UA 1878 as 89.1% on time with 1.83% cancelled over 328 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- AUS to ORD, every carrier and departure
- ORD to AUS, the return direction
- American Airlines 1726 on the same route78.1%
- United Airlines 1990 on the same route57.2%
- Austin-Bergstrom International (AUS) 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
- Worst months to fly in the US, ranked by the data
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, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.