Route profile
BWI→IAH
Flight reliability, delays and best times to fly from Baltimore to Houston, 1,235 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 47% of comparable major US routes (4,598 compared)
Calculated from 3,633 flights. How this is calculated · What counts as on time
BWI → IAH arrives on time 79.6% of the time; the return trip, IAH → BWI, arrives on time 77.3% of the time, a 2.3-point gap between the two directions of the same city pair.
BWI → IAH spends 25.9 minutes on the ground on a 1,235-mile trip: 14.6 minutes from pushback to wheels-up at BWI and 11.4 minutes from touchdown to gate at IAH.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What sets this route apart
Where BWI to IAH differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
BWI to IAH is at its best against routes of similar length for flights scheduled at 8 PM: 75.8% arrive on time, 10.8 points ahead of the 65.0% those routes manage at that hour.
BWI to IAH struggles most at 5 PM: 59.3% of its flights scheduled then arrive on time, 8.9 points behind the 68.2% on routes of similar length at the same hour. Against all other routes the gap is 10.5 points.
BWI to IAH holds up on Thursdays better than routes of similar length do: 82.3% on time to their 75.9%, a 6.4 points lead. Against all other routes the gap is 5.5 points.
March is kinder to BWI to IAH than to routes of similar length: 85.6% on time against 75.8%, 9.8 points better. Against all other routes the gap is 7.7 points.
United Airlines does better on BWI to IAH than on its routes of similar length: 83.4% on time here, 80.9% there, 2.5 points apart. Against all other routes the gap is 3.5 points.
BWI to IAH against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 8 PM departures | 75.8% | routes of similar length | 65.0% | +10.8 pts | 124 here, 84,578 there |
| Hour: 5 PM departures | 59.3% | routes of similar length | 68.2% | −8.9 pts | 123 here, 117,859 there |
| Weekday: Thursday | 82.3% | routes of similar length | 75.9% | +6.4 pts | 558 here, 283,290 there |
| Month: March | 85.6% | routes of similar length | 75.8% | +9.8 pts | 236 here, 170,328 there |
| Airline: United Airlines | 83.4% | routes of similar length | 80.9% | +2.5 pts | 2,116 here, 284,673 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,235 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
Why BWI → IAH flights are cancelled
July 2023 – July 2026
BWI → IAH cancelled 58 of 3,633 scheduled flights — about 1 in every 63. The reason filed most often was extreme weather, 60.3% of the cancellations coded on this route — about 1 in every 104 scheduled flights.
Share of cancellations
Of 58 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
35 cancellations, 60.3% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
21 cancellations, 36.2% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
2 cancellations, 3.4% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. With only one or two carriers on the route, the split mostly reflects how they file. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
58 coded cancellations were recorded on BWI → IAH; the section appears from 50.
When it goes wrong
July 2023 – July 2026
39 min late
against a median of 8 min early
Percentiles over 3,633 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at IAH after arriving from BWI.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 34% | Likely to miss |
| 45 min | 20% | High risk |
| 60 min | 13% | Some risk |
| 90 min | 7.1% | Some risk |
| 120 min | 4.8% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 1.60% of the time and diverts 0.36% of the time, which a late arrival never shows up in.
Chance of missing is the share of 3,562 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 39 minutes late (90th-percentile gate arrival delay), over 3,633 operations.
Any other layover length: connection checker.
Best time to fly
BWI → IAH flights departing 5–9 AM arrived on time 89.2% of the time, against 67.8% for 6–9 PM departures, a gap of 21.4 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 91.2% on time from 926 flights
- 7 AM: too few flights to score
- 8 AM: 85.2% on time from 325 flights
- 9 AM to 10 AM: too few flights to score
- 11 AM: 79.2% on time from 131 flights
- 12 PM: 81.9% on time from 338 flights
- 1 PM: too few flights to score
- 2 PM: 76.6% on time from 359 flights
- 3 PM: 70.7% on time from 211 flights
- 4 PM: 73.5% on time from 317 flights
- 5 PM: 59.3% on time from 126 flights
- 6 PM: 64.8% on time from 194 flights
- 7 PM: 64.3% on time from 120 flights
- 8 PM: 75.8% on time from 128 flights
- 9 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why BWI → IAH runs late
July 2023 – July 2026
airspace and airport capacity, including weather-driven flow control
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for BWI → IAH. Only delays of 15 minutes or more are attributed. What the five causes mean
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 2,149 | 83.4% | 1.16% | -9 min | 5.1% |
| Spirit Airlines | 1,334 | 75.4% | 1.80% | -7 min | 9.6% |
United Airlines flew 61.7% of the 3,483 flights listed.
United Airlines arrived on time 8.0 percentage points more often than Spirit Airlines on this route.
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Monday the least, a gap of 7.0 percentage points.
By month
- Jan: 82.7%
- Feb: 88.4%
- Mar: 85.6%
- Apr: 75.6%
- May: 70.1%
- Jun: 69.2%
- Jul: 69.8%
- Aug: 78.6%
- Sep: 84.8%
- Oct: 90.7%
- Nov: 84.6%
- Dec: 80.8%
June is historically the weakest month and October the strongest, a spread of 21.5 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: too few flights to score (77)
- August 2023: too few flights to score (81)
- September 2023: too few flights to score (82)
- October 2023: too few flights to score (88)
- November 2023: too few flights to score (89)
- December 2023: too few flights to score (74)
- January 2024: too few flights to score (72)
- February 2024: too few flights to score (65)
- March 2024: too few flights to score (62)
- April 2024: too few flights to score (101)
- May 2024: too few flights to score (109)
- June 2024: too few flights to score (115)
- July 2024: too few flights to score (98)
- August 2024: 71.4% from 120 flights
- September 2024: too few flights to score (110)
- October 2024: too few flights to score (108)
- November 2024: too few flights to score (109)
- December 2024: too few flights to score (113)
- January 2025: too few flights to score (111)
- February 2025: too few flights to score (79)
- March 2025: too few flights to score (66)
- April 2025: too few flights to score (90)
- May 2025: too few flights to score (103)
- June 2025: too few flights to score (95)
- July 2025: too few flights to score (106)
- August 2025: too few flights to score (100)
- September 2025: too few flights to score (106)
- October 2025: too few flights to score (108)
- November 2025: 81.0% from 123 flights
- December 2025: too few flights to score (104)
- January 2026: too few flights to score (119)
- February 2026: too few flights to score (102)
- March 2026: too few flights to score (115)
- April 2026: too few flights to score (119)
- May 2026: too few flights to score (106)
- June 2026: too few flights to score (103)
- July 2026: too few flights to score (105)
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 79.4% against 81.9% in the 12 months before — declining by 2.5 percentage points.
Data and methodology
Calculated by FlyerIntel from 3,633 BWI → IAH flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed