PlainFlights

Route · ISP → BWI · 2020–2025 BTS data

Islip to Baltimore

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), ISP to BWI (Islip to Baltimore) ranks #1715 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

88.3%
On-time
+9.3 pts
vs US avg
70 min
Delay when late
7,390
Flights
#1715 of 4927
Corpus placement

Cancelled

0.8%

Best Month

Sep 2025 96%

Worst Month

Jul 2025 75%

Distance

220 mi

Carriers

1

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 93 21 0 0 WN
Nov 2025 90 11 2 0 WN
Oct 2025 93 10 0 0 WN
Sep 2025 90 4 0 0 WN
Aug 2025 97 19 0 0 WN
Jul 2025 128 32 3 2 WN
Jun 2025 123 26 0 0 WN
May 2025 114 27 0 0 WN
Apr 2025 106 10 0 0 WN
Mar 2025 89 11 2 0 WN
Feb 2025 82 4 0 0 WN
Jan 2025 89 9 1 0 WN
Dec 2024 94 8 1 0 WN
Nov 2024 89 6 0 0 WN
Oct 2024 93 6 0 0 WN
Sep 2024 94 6 0 0 WN
Aug 2024 100 25 0 0 WN
Jul 2024 127 31 4 0 WN
Jun 2024 121 17 0 0 WN
May 2024 116 20 0 0 WN
Apr 2024 111 16 0 1 WN
Mar 2024 108 17 0 0 WN
Feb 2024 97 7 2 0 WN
Jan 2024 112 16 4 0 WN

ISP–BWI seasonal on-time pattern

Best: February (94.5%) · weakest: July (81.6%)

80%85%90%95%100% JanFebMarAprMayJunJulAugSepOctNovDec 86.7%

Strongest calendar month

February

94.5% on-time · ~84 flights/mo

Busiest calendar month

July

~118 flights/mo avg

Weakest calendar month

July

81.6% on-time · ~118 flights/mo

Cancellation Rate

0.8%

19 of 2,456 flights

Diversion Rate

0.1%

3 of 2,456 flights

Origin-hub reliability standing

Among ISP's stronger departures

ISP → BWI posts a 88.3% on-time rate, landing in the ≥85% band with 1 of 5 BTS-tracked routes leaving Islip. The same hub also shows 3 mid-band and 1 challenged departures · fleet-wide on-time rank #364 of 4927 (highest on-time = #1).

What the Data Says About ISP to BWI

Islip to Baltimore (ISP to BWI) is one of the more dependable pairings in the BTS On-Time Performance dataset: a 88.3% on-time rate across 7,390 flights, with delays that do happen averaging 69.7 minutes. The corridor runs roughly 220 miles and is served by 1 carrier. Over the most recent 24 months, 19 of 2,456 flights were cancelled (0.8%) and 3 diverted (0.1%).

The monthly split is wide on this route: Sep 2025 posted the strongest performance at 96% on-time, while Jul 2025 came in at just 75% - a 21-point swing worth factoring into travel timing.

On the multi-year calendar, ISP–BWI peaks in February at 94.5% on-time while July carries the heaviest traffic (~118 flights per month) ; the softest month is July at 81.6%, a 12.9-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does ISP to BWI rank among US routes by traffic?
According to PlainFlights' route traffic ranking, ISP to BWI ranks #1715 of 4927 tracked domestic routes by total flights (most flights = #1). That ordinal matches our busiest-routes listing (total_flights DESC). See /methodology#corpus-placement for the exact sort basis.
How often are flights delayed from ISP to BWI?
Flights from Islip to Baltimore have a 88.3% on-time rate based on 7,390 flights. The average delay is 69.7 minutes. The best recent month was Sep 2025 with 96% on-time.
What is the cancellation rate for ISP to BWI?
Over the last 24 months, 0.8% of flights on this route were cancelled (19 of 2,456 flights) and 0.1% were diverted.
How far is the flight from ISP to BWI?
The flight distance from Islip (ISP) to Baltimore (BWI) is approximately 220 miles. This route is served by 1 carrier.
When is the best time to fly from ISP to BWI?
The best recent month for on-time performance was Sep 2025 (96% on-time). The worst was Jul 2025 (75% on-time). Consider booking during months with historically better performance.

Airports on this route

Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Using ISP–BWI data

ISP–BWI runs 9.3 pts above the national 79% average; the remaining risk is month-to-month swing and carrier mix, not a weak headline rate.

  • Compare ISP and BWI airport profiles: delay causes and top routes differ even on the same corridor. ISP airport
  • If your dates flex, February (94.5% on-time) beats July (81.6%) on this corridor. Seasonal chart
  • 4 other routes post a similar 88.3% on-time rate; compare before you commit to this pairing. Similar routes

On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.