What is the cheapest month to fly from Islip to Dulles?

Based on current 6-month forward fare data, May 2026 is the cheapest month to fly from Islip (ISP) to Dulles (IAD), with fares starting from $153.

What is the lowest current fare from ISP to IAD?

The lowest currently-listed fare from Islip (ISP) to Dulles (IAD) is $153 on 2026-05-29.

Is there a direct flight from Islip to Dulles?

There is currently no non-stop service from ISP to IAD. Most travellers connect through a hub airport. See our route page for current stopover options.

Cheap flights from Islip to Dulles

Cheapest current fares: $153 in May 2026 on connecting flights.

Last updated May 24, 2026 · By Flightmaps Editorial

Cheapest month-by-month fares

Lowest available fare per calendar month from Islip (ISP) to Dulles (IAD). Refreshed daily.

Islip (ISP) → Dulles (IAD)

May 2026 $153

Frequently asked questions

What is the cheapest month to fly from Islip to Dulles?

Based on current 6-month forward fare data, May 2026 is the cheapest month to fly from Islip (ISP) to Dulles (IAD), with fares starting from $153.
What is the lowest current fare from ISP to IAD?

The lowest currently-listed fare from Islip (ISP) to Dulles (IAD) is $153 on 2026-05-29.
Is there a direct flight from Islip to Dulles?

There is currently no non-stop service from ISP to IAD. Most travellers connect through a hub airport. See our route page for current stopover options.

Related guides for this route

Sibling pages — full route detail, airport overviews, visa context, per-airline routes.