Carrier route record
UASTL→EWR
United Airlines · St. Louis to Newark
- Flights
- 127
- Period
- July 2025 to June 2026
- Share of route
- 12%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on STL to EWR draws a C+. About one flight in three arrives at least 15 minutes late, and the typical late arrival is an hour and a half behind schedule. Build slack into anything you connect to. That rests on 127 flights, with a median arrival 3 minutes early.
The national on-time rate over the same period is 77.6%, so United on STL to EWR runs 12 points behind the country as a whole. Across a thousand flights that is about 122 extra late arrivals.
Key figures
On time
65.4%
Arrivals under 15 minutes late, of 127 completed flights
Avg delay
91 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.81%
Whole route
81.3%
Every carrier on STL to EWR, 1,075 flights
These figures cover 127 flights between July 2025 and June 2026. Beyond the headline rate, 14.2% 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.
Carrier by carrier
United against every carrier on STL to EWR
United flew 127 of the 1,075 flights on STL to EWR, about 12% of it. Its 65.4% on time is 16 points worse than the route as a whole, which runs 81.3%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from Republic at 83.6% to United at 65.4%.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airways | 948 | 83.6% | 94 min | 5.17% | B− |
| United Airlines (this page)thin sample | 127 | 65.4% | 91 min | 0.00% | C+ |
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 44 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am56 flights92.9%
- 8am–11am—
- 11am–2pm45 flights48.9%
- 2pm–5pm—
- 5pm–8pm26 flights—
- 8pm–5am—
Scale runs 40% to 100%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 48.9% on time against 92.9% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 5am–8am window is the busiest, with 56 flights scheduled in it.
Across the year
United on STL to EWR through the year
- Jul–Sep 20255 flights—
- Oct–Dec 202578 flights50.0%
- Jan–Mar 20264 flights—
- Apr–Jun 202640 flights92.5%
Scale runs 40% to 100%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 65.4% on time across 127 flights.
Split by quarter, United on STL to EWR logged 5 flights in Jul–Sep 2025, 78 flights in Oct–Dec 2025, 4 flights in Jan–Mar 2026 and 40 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 65.4% annual figure is the one to use.
Delay causes
Why United runs late on this route
One category carries most of the weight here. National Airspace System accounts for 58% of the 4,011 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.
- 58%National Airspace System
- 29%Late-arriving aircraft
- 12%Carrier
- 1%Extreme weather
58% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 2,321 minutes out of 4,011, against a national NAS share of 21%. The split is drawn from 4,011 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 92.9% on time here.
Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 14.2% 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 872 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 return leg is a different operation and performs like one: it runs 71.7% on time across 128 flights, 6 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 6 points of difference.
One caution: this is a thin sample. 127 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 United on STL to EWR
Put together: treat all of this as provisional. 127 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 65.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 127 completed flights over 12 months sit behind that.
Related
Where to go next
- STL to EWR, every carrier
- United on EWR to STL, the return leg
- Republic Airways on STL to EWR83.6%
- United Airlines network-wide record
- St. Louis Lambert International (STL) delay statistics
- Newark Liberty International (EWR) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- How often a connection fails at the major US hubs
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.