Carrier route record

NKBWI→IAH

Spirit Airlines · Baltimore to Houston

Flights: 293
Period: September 2025 to August 2026
Share of route: 22%
Carriers: 4

Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Spirit Airlines.

Spirit on BWI to IAH sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.3%. The late ones land close to two hours behind schedule. That rests on 293 flights, with a median arrival 9 minutes early.

The national on-time rate over the same period is 77.3%, so Spirit on BWI to IAH runs 4 points behind the country as a whole. Across a thousand flights that is about 40 extra late arrivals.

On time

73.3%

Arrivals under 15 minutes late, of 285 completed flights

Avg delay

103 min

Across delayed arrivals only, not all flights

Cancelled

2.73%

National rate is 1.89%

Whole route

78.3%

Every carrier on BWI to IAH, 1,307 flights

These figures cover 293 flights between September 2025 and August 2026. Beyond the headline rate, 13.0% of arrivals land a full hour or more behind schedule, against 8.3% nationally.

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Carrier by carrier

Spirit against every carrier on BWI to IAH

Spirit flew 293 of the 1,307 flights on BWI to IAH, about 22% of it. Its 73.3% on time is 5 points worse than the route as a whole, which runs 78.3%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from SkyWest at 100.0% to Frontier at 59.1%. Two 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 BWI to IAH
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlinesthin sample	1	100.0%	—	0.00%	A+
United Airlines	833	84.0%	68 min	1.20%	B
Spirit Airlines (this page)thin sample	293	73.3%	103 min	2.73%	C
Frontier Airlinesthin sample	180	59.1%	90 min	5.00%	D−

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.

Departure window

When Spirit runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 22 points, against half a point between the best and worst carrier.

5am–8am42 flights83.3%
8am–11am18 flights—
11am–2pm61 flights77.0%
2pm–5pm15 flights—
5pm–8pm70 flights61.8%
8pm–5am87 flights69.1%

Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 61.8% on time, against 83.3% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8pm–5am window is the busiest, with 87 flights scheduled in it.

Across the year

Spirit on BWI to IAH through the year

Jul–Sep 202546 flights84.8%
Oct–Dec 2025137 flights78.8%
Jan–Mar 202687 flights65.0%
Apr–Jun 202623 flights—

Scale runs 55% to 90%. 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 73.3% on time across 293 flights.

Spirit on BWI to IAH did not run the same all year. Its best quarter was Jul–Sep 2025 at 84.8% on time and its weakest Jan–Mar 2026 at 65.0%, a swing of 20 points on roughly 98 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.

Across the week, Wednesday is the strongest day at 84.4% on time and Monday the weakest at 63.3%, a spread of 21 points.

Arrival by arrival

How late Spirit on BWI to IAH runs when it is late

Spirit on BWI to IAH often beats the schedule: 119 of 285 completed flights, 42%, arrived 15 minutes or more early. The 76 late arrivals split 19 under half an hour, 20 between 30 and 60 minutes, and 37 an hour or more.

15+ min early119 flights41.8%
Within 15 min90 flights31.6%
15–29 min late19 flights6.7%
30–59 min late20 flights7.0%
1–2 hours late19 flights6.7%
2+ hours late18 flights6.3%

Scale runs 0% to 100%.

Share of 285 completed flights by arrival against schedule.

22 of 91 late departures made up the time and arrived on time, 24% of them. 7 flights left on time and still arrived late.

The worst days

Worst days for Spirit on BWI to IAH

The latest arrival of the period was on 1 April 2026, 16 hours 45 minutes behind schedule; most of its delay minutes were filed as national airspace system delay. The five worst days are spread across April, March, September and February, with no single month standing out.

The latest arrivals of Spirit on BWI to IAH in the period
Date	Arrived late by	Largest filed cause
1 April 2026	16 hours 45 minutes	National Airspace System
20 March 2026	14 hours 13 minutes	Carrier
7 September 2025	4 hours 54 minutes	Extreme weather
16 February 2026	4 hours 35 minutes	Carrier
4 September 2025	4 hours 25 minutes	National Airspace System

Delay causes

Why Spirit runs late on this route

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 7,861 reported delay minutes.

National Airspace System
35%
Carrier
33%
Late-arriving aircraft
28%
Extreme weather
5%
Security
0%

35% 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 2,713 minutes out of 7,861, against a national NAS share of 21%. The split is drawn from 7,861 reported delay minutes.

Cancellations run at 2.73%, against 1.89% nationally. That is roughly one flight in 40 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

13.0% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.

The 1,235 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 is a different operation and performs like one: it runs 79.9% on time across 295 flights, 7 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 7 points of difference.

One caution: this is a thin sample. 293 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 Spirit on BWI to IAH

Put together: treat all of this as provisional. 293 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 73.3% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 285 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures