Carrier route record

YXDCA→IAH

Republic Airways · Washington to Houston

Flights: 511
Period: July 2025 to June 2026
Share of route: 16%
Carriers: 3

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Republic Airways.

Republic on DCA to IAH sits in the middle of the pack with a B−. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 511 flights, with a median arrival 9 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate Republic on DCA to IAH from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

75.7%

Arrivals under 15 minutes late, of 485 completed flights

Avg delay

56 min

Across delayed arrivals only, not all flights

Cancelled

5.09%

National rate is 1.81%

Whole route

81.4%

Every carrier on DCA to IAH, 3,200 flights

These figures cover 511 flights between July 2025 and June 2026. Beyond the headline rate, 8.0% 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

Republic against every carrier on DCA to IAH

Republic flew 511 of the 3,200 flights on DCA to IAH, about 16% of it. Its 75.7% on time is 6 points worse than the route as a whole, which runs 81.4%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from United at 83.8% to PSA at 70.1%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

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.

On-time performance by carrier on DCA to IAH
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	2,413	83.8%	95 min	0.91%	B+
Republic Airways (this page)	511	75.7%	56 min	5.09%	B−
PSA Airlinesthin sample	276	70.1%	73 min	5.43%	C−

Departure window

When Republic runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 21 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–8am120 flights91.2%
8am–11am8 flights—
11am–2pm2 flights—
2pm–5pm179 flights69.8%
5pm–8pm12 flights—
8pm–5am190 flights72.2%

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 91.2% of the time, against 69.8% for the afternoon window. That is 21 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 190 flights scheduled in it.

Across the year

Republic on DCA to IAH through the year

Jul–Sep 202570 flights74.3%
Oct–Dec 2025235 flights75.7%
Jan–Mar 2026196 flights76.0%
Apr–Jun 202610 flights—

Scale runs 65% to 80%. 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 75.7% on time across 511 flights.

Quarter by quarter Republic on DCA to IAH held fairly steady: 74.3% in Jul–Sep 2025, 75.7% in Oct–Dec 2025 and 76.0% in Jan–Mar 2026. A spread of 2 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Across the week, Monday is the strongest day at 81.6% on time and Sunday the weakest at 70.0%. 12 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Republic runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 49% of the 6,661 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.

Late-arriving aircraft
49%
National Airspace System
27%
Carrier
19%
Extreme weather
6%

49% 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 6,661 reported delay minutes here, that single category outweighs weather by 9 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 6,661 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 91.2% on time here.

Cancellations run at 5.09%, against 1.81% 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 costs

8.0% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.

The 1,208 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 runs 75.9% on time across 513 flights, within half 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. 511 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 Republic on DCA to IAH

Put together: the delay figures matter less here than the 5.09% cancellation rate. A late arrival costs you about an hour; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 485 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures