Route reliability record
IAD→LGA
Washington to New York
- Flights
- 980
- Period
- July 2025 to June 2026
- Distance
- 228 mi
- Carriers
- 1
This route carries a cancellation problem, not just a delay problem: 6.5% of scheduled flights never operate, against 1.8% nationally. Of the ones that do fly, close to three flights in four arrive on time, worth a C− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 980 IAD to LGA flights, with a median arrival 5 minutes early.
Best time to fly IAD to LGA: a 8am–11am departure, ideally on a Saturday. Flights in that window arrived on time 85.3% of the time and Saturday flights 86.9%, against 73.8% for the route overall.
The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
73.8%
Arrivals under 15 minutes late, of 915 completed flights
Avg delay
71 min
Across delayed arrivals only, not all flights
Cancelled
6.53%
National rate is 1.81%
Best carrier
Republic
73.8% on time across 980 flights
These figures cover 980 flights between July 2025 and June 2026. Beyond the headline rate, 9.8% 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
Which airline is most reliable on IAD to LGA
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 | 980 | 73.8% | 71 min | 6.53% | C− |
Best ways to make this trip
The most reliable ways to fly Washington to New York
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. 4 of the top 5 use a different airport at one end.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. DCA → JFKWashington to New York | JetBlue Airways | 77.1% | 81.9% | 5.83% | 5am–8am, Wed | — |
| 2. BWI → ISPBaltimore to Islip | Southwest Airlines | 76.0% | 77.5% | 1.97% | 11am–2pm, Fri | — |
| 3. IAD → EWRWashington to Newark | United Airlines | 73.5% | 75.2% | 2.23% | 5am–8am, Wed (route) | UA 2669 06:00 |
| 4. DCA → JFKWashington to New York | Republic Airways | 73.1% | 77.2% | 5.37% | 5am–8am, Sat | YX 5713 17:00 |
| 5. IAD → LGAWashington to New York | Republic Airways | 69.0% | 73.8% | 6.53% | 8am–11am, Sat | — |
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 18 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–8am—
- 8am–11am122 flights85.3%
- 11am–2pm334 flights66.9%
- 2pm–5pm—
- 5pm–8pm242 flights72.6%
- 8pm–5am282 flights77.9%
Scale runs 60% to 90%. 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 66.9% on time against 85.3% for 8am–11am. 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 11am–2pm window is the busiest, with 334 flights scheduled in it.
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 58.3% on time, 28 points below January, the best at 86.7%. 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 111 flights.
Across the week, Saturday is the strongest day at 86.9% on time and Thursday the weakest at 68.7%. 18 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. National Airspace System accounts for 57% of the 17,000 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.
- 57%National Airspace System
- 24%Late-arriving aircraft
- 18%Carrier
- 1%Extreme weather
57% 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 9,676 minutes out of 17,000, against a national NAS share of 21%. The split is drawn from 16,964 reported delay minutes.
Cancellations run at 6.53%, against 1.81% nationally. That is about one flight in fifteen 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
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.8% 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.
At 228 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.
The return leg runs 75.4% on time across 980 flights, within 2 points 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. 980 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 LGA after this flight
What to do with this
Booking this route
Put together: the delay figures matter less here than the 6.53% 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. 915 completed flights over 12 months sit behind that.
Common questions
IAD to LGA questions
How often is IAD to LGA delayed?
About one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 26.2% of the 980 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
How reliable is IAD to LGA compared with the rest of the country?
73.8% of flights arrive on time here against a national 77.6%, a difference of 4 points against it. That is worth a C− on this site's grading scale.
What time of day has the fewest delays on IAD to LGA?
The 8am–11am departure window is the strongest at 85.3% on time. The 11am–2pm window is the weakest at 66.9%, 18 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 IAD to LGA?
July is the weakest month at 58.3% on time, compared with 86.7% in January. 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
- LGA to IAD — the return legseparate record
- Washington Dulles International (IAD) delay statistics
- LaGuardia (LGA) delay statistics
- IAD to ATL, a related route79.2%
- ORD to LGA, a related route67.3%
- IAD to DEN, a related route81.7%
- Republic Airways on-time record73.8%
- The US routes with the most cancellations
- What a cancellation rate actually tells you (and what it hides)
Direction matters. IAD to LGA and LGA to IAD are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed IAD to LGA’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
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.