Route reliability record
EWR→STL
Newark to St. Louis
- Flights
- 1,074
- Period
- September 2025 to August 2026
- Distance
- 872 mi
- Carriers
- 2
This route carries a cancellation problem, not just a delay problem: 5.4% of scheduled flights never operate, against 1.9% nationally. Of the ones that do fly, more than four flights in five arrive on time, worth a B− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 1,074 EWR to STL flights, with a median arrival 13 minutes early.
Best time to fly EWR to STL: a 8am–11am departure, ideally on a Tuesday. Flights in that window arrived on time 88.2% of the time and Tuesday flights 86.6%, against 82.8% for the route overall.
Set against the rest of the country, this route's record is 6 points better than the US average of 77.3%. That gap is worth roughly 55 fewer late arrivals for every thousand flights.
Key figures
On time
82.8%
Arrivals under 15 minutes late, of 1,014 completed flights
Avg delay
68 min
Across delayed arrivals only, not all flights
Cancelled
5.40%
National rate is 1.89%
Best carrier
Republic
86.8% on time across 866 flights
These figures cover 1,074 flights between September 2025 and August 2026. The median arrival is 13 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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Carrier by carrier
Which airline is most reliable on EWR to STL
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 | 866 | 86.8% | 65 min | 5.54% | A− |
| United Airlinesthin sample | 208 | 66.7% | 73 min | 4.81% | C− |
Flight by flight
Flights on EWR to STL
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Best ways to make this trip
The most reliable ways to fly Newark to St. Louis
Every airline on this route and on the routes between nearby airports, ranked by how often a scheduled flight actually operated and arrived on time. 2 of the top 3 use a different airport at one end.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. EWR → STLNewark to St. Louis | Republic Airways | 82.0% | 86.8% | 5.54% | 8am–11am, Fri | YX 3630 09:00 |
| 2. LGA → STLNew York to St. Louis | Republic Airways | 73.1% | 77.5% | 5.62% | 5am–8am, Wed | — |
| 3. LGA → STLNew York to St. Louis | Southwest Airlines | 70.5% | 73.3% | 3.80% | 5am–8am, Wed | — |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 15 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am361 flights88.2%
- 11am–2pm—
- 2pm–5pm331 flights87.5%
- 5pm–8pm19 flights—
- 8pm–5am363 flights73.3%
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 88.2% of the time, against 73.3% for the overnight window. That is 15 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8pm–5am window is the busiest, with 363 flights scheduled in it.
Explore
Filter EWR to STL by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On EWR to STL, the best departure window is 8am–11am at 88.2% on time and the worst is 8pm–5am at 73.3%, a wide gap of 14.9 points. All US flights leaving 8am–11am ran 83.9%.
- 5–8am—
- 8–11am88.2%
- 11am–2pm—
- 2–5pm87.5%
- 5–8pm—
- 8pm–5am73.3%
best all US flightsScale 60% to 95%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 28 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 68.8% on time, 28 points below April, the best at 96.5%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. September was the busiest month here, with 106 flights.
Across the week, Tuesday is the strongest day at 86.6% on time and Saturday the weakest at 76.4%, a spread of 10 points.
Delay causes
Why this route gets delayed
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.
- 39%Late-arriving aircraft
- 28%Carrier
- 24%National Airspace System
- 9%Extreme weather
39% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 12,000 reported delay minutes here, that single category outweighs weather by 5 to one. The split is drawn from 11,845 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 88.2% on time here.
Cancellations run at 5.40%, against 1.89% nationally. That is about one flight in twenty cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here actually costs
6.3% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
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.
The return leg runs 81.4% on time across 1,075 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 1,074 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.
Work out the risk of missing a connection in STL after this flight
What to do with this
Booking this route
Put together: the delay figures matter less here than the 5.40% cancellation rate. A late arrival costs you a little over an hour; a cancelled flight costs you the day. Book the 8am–11am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 1,014 completed flights over 12 months sit behind that.
Common questions
EWR to STL questions
How often is EWR to STL delayed?
About one flight in six arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 17.2% of the 1,074 flights in this analysis, against 22.7% nationally. Delayed flights are late by a little over an hour on average.
How reliable is EWR to STL compared with the rest of the country?
82.8% of flights arrive on time here against a national 77.3%, a difference of 6 points in its favour. That is worth a B− on this site's grading scale.
What time of day has the fewest delays on EWR to STL?
The 8am–11am departure window is the strongest at 88.2% on time. The 8pm–5am window is the weakest at 73.3%, 15 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on EWR to STL?
July is the weakest month at 68.8% on time, compared with 96.5% in April. Across the year that is 28 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- STL to EWR — the return legseparate record
- Newark Liberty International (EWR) delay statistics
- St. Louis Lambert International (STL) delay statistics
- Republic Airways on EWR to STL86.8%
- United Airlines on EWR to STL66.7%
- EWR to MCO, a related route77.9%
- DEN to STL, a related route77.7%
- EWR to ATL, a related route76.9%
- Republic Airways on-time record86.8%
- United Airlines on-time record66.7%
- The US routes with the most cancellations
- Why the first flight of the morning is statistically safest
Direction matters. EWR to STL and STL to EWR are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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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.