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Flights from Islip to Washington D.C.

Search cheap flights from Islip to Washington D.C. in the next 3 months. Based on Trip.com's latest 7-day data, one-way fares start at INR 6,095, and round-trip tickets start at INR 25,325.

      • ISP 16:05
        16h 21m
        1 stop
        IAD 08:26
        Islip - Washington D.C. | Sat, Dec 13 | Frontier Airlines
        IAD 09:26
        14h 33m
        1 stop
        ISP 23:59
        Washington D.C. - Islip | Mon, Dec 15 | Frontier Airlines
        INR 25,325 INR 73,961
        66% OFF
        66% OFF
        INR 73,961 INR 25,325
      • ISP 12:25
        6h 53m
        1 stop
        DCA 19:18
        Islip - Washington D.C. | Tue, Feb 3 | Jetblue Airways
        DCA 12:15
        20h 40m
        1 stop
        ISP 08:55
        Washington D.C. - Islip | Wed, Feb 4 | Jetblue Airways
        INR 28,245 INR 73,961
        62% OFF
        62% OFF
        INR 73,961 INR 28,245
      • ISP 18:40
        26h 23m
        1 stop
        IAD 21:03
        Islip - Washington D.C. | Sat, Dec 20 | Frontier Airlines
        IAD 22:15
        14h 54m
        1 stop
        ISP 13:09
        Washington D.C. - Islip | Sat, Dec 27 | Frontier Airlines
        INR 31,548 INR 73,961
        56% OFF
        56% OFF
        INR 73,961 INR 31,548
      • ISP 12:25
        10h 6m
        1 stop
        DCA 22:31
        Islip - Washington D.C. | Wed, Jan 14 | Jetblue Airways
        DCA 18:30
        17h 5m
        1 stop
        ISP 11:35
        Washington D.C. - Islip | Tue, Jan 20 | Jetblue Airways
        INR 35,094
        53% OFF
        INR 73,961 INR 35,094
      • ISP 13:27
        10h 2m
        1 stop
        DCA 23:29
        Islip - Washington D.C. | Fri, Dec 19 | Frontier Airlines
        DCA 06:40
        13h
        1 stop
        ISP 19:40
        Washington D.C. - Islip | Mon, Dec 22 | American Airlines
        INR 38,551
        48% OFF
        INR 73,961 INR 38,551
      • ISP 06:00
        27h 48m
        1 stop
        IAD 09:48
        Islip - Washington D.C. | Thu, Dec 18 | Frontier Airlines
        IAD 21:58
        15h 11m
        1 stop
        ISP 13:09
        Washington D.C. - Islip | Sun, Dec 21 | Frontier Airlines
        INR 43,647
        41% OFF
        INR 73,961 INR 43,647
      • ISP 10:46
        10h 17m
        1 stop
        IAD 21:03
        Islip - Washington D.C. | Mon, Dec 22 | Jetblue Airways
        IAD 21:58
        12h 3m
        1 stop
        ISP 10:01
        Washington D.C. - Islip | Fri, Dec 26 | Frontier Airlines
        INR 48,845
        34% OFF
        INR 73,961 INR 48,845
      • ISP 12:40
        25h 54m
        1 stop
        DCA 14:34
        Islip - Washington D.C. | Fri, Jan 16 | Cape Air
        DCA 18:30
        17h 5m
        1 stop
        ISP 11:35
        Washington D.C. - Islip | Mon, Jan 19 | Jetblue Airways
        INR 51,828
        30% OFF
        INR 73,961 INR 51,828
      • ISP 09:40
        8h 20m
        1 stop
        DCA 18:00
        Islip - Washington D.C. | Fri, Jan 16 | Jetblue Airways
        DCA 18:30
        17h 5m
        1 stop
        ISP 11:35
        Washington D.C. - Islip | Mon, Jan 19 | Jetblue Airways
        INR 52,763
        28% OFF
        INR 73,961 INR 52,763
      • ISP 19:40
        13h 24m
        1 stop
        DCA 09:04
        Islip - Washington D.C. | Sun, Dec 21 | Jetblue Airways
        DCA 07:00
        27h 1m
        1 stop
        ISP 10:01
        Washington D.C. - Islip | Thu, Dec 25 | Jetblue Airways
        INR 53,992
        27% OFF
        INR 73,961 INR 53,992
      • ISP 13:00
        17h 25m
        1 stop
        WAS Invalid Date
        Islip - Washington D.C. | Sun, Dec 14 | Normal Airline
        WAS 15:00
        6h
        Nonstop
        ISP 16:00
        Washington D.C. - Islip | Tue, Dec 16 | Normal Airline
        Find More Flights
        Find More Flights
      • ISP 15:34
        23h 4m
        1 stop
        IAD 14:38
        Islip - Washington D.C. | Sat, Jan 10 | Frontier Airlines
        INR 6,095 INR 18,328
        67% OFF
        67% OFF
        INR 18,328 INR 6,095
      • ISP 06:15
        13h 52m
        1 stop
        DCA 20:07
        Islip - Washington D.C. | Tue, Dec 16 | Frontier Airlines
        INR 7,542 INR 18,328
        59% OFF
        59% OFF
        INR 18,328 INR 7,542
      • ISP 16:40
        25h 55m
        1 stop
        DCA 18:35
        Islip - Washington D.C. | Sat, Dec 20 | Frontier Airlines
        INR 10,474 INR 18,328
        43% OFF
        43% OFF
        INR 18,328 INR 10,474
      • ISP 21:09
        10h 26m
        1 stop
        IAD 07:35
        Islip - Washington D.C. | Sat, Dec 13 | Frontier Airlines
        INR 11,511
        37% OFF
        INR 18,328 INR 11,511
      • ISP 11:50
        10h 49m
        1 stop
        DCA 22:39
        Islip - Washington D.C. | Tue, Dec 16 | Jetblue Airways
        INR 11,780
        36% OFF
        INR 18,328 INR 11,780
      • ISP 20:35
        24h 28m
        1 stop
        IAD 21:03
        Islip - Washington D.C. | Sun, Dec 21 | Frontier Airlines
        INR 12,279
        33% OFF
        INR 18,328 INR 12,279
      • ISP 09:40
        28h 58m
        1 stop
        IAD 14:38
        Islip - Washington D.C. | Sat, Jan 10 | Jetblue Airways
        INR 12,573
        31% OFF
        INR 18,328 INR 12,573
      • ISP 05:45
        14h 11m
        1 stop
        DCA 19:56
        Islip - Washington D.C. | Fri, Dec 19 | Frontier Airlines
        INR 12,727
        31% OFF
        INR 18,328 INR 12,727
      • ISP 05:45
        12h 9m
        1 stop
        DCA 17:54
        Islip - Washington D.C. | Thu, Dec 18 | Frontier Airlines
        INR 12,791
        30% OFF
        INR 18,328 INR 12,791
      • ISP 20:35
        24h 28m
        1 stop
        IAD 21:03
        Islip - Washington D.C. | Mon, Dec 22 | Frontier Airlines
        INR 13,380
        27% OFF
        INR 18,328 INR 13,380
      • ISP 13:00
        17h 25m
        1 stop
        WAS Invalid Date
        Islip - Washington D.C. | Sun, Dec 14 | Normal Airline
        Find More Flights
        Find More Flights

Displayed flight fares from Islip to Washington D.C. are based on average prices across airlines for the next 3 months, according to the latest Trip.com database.

Islip to Washington D.C. Flight Details

The distance between Islip and Washington D.C. is about 397.38 km. Based on Trip.com's latest data, travel demand is highest in July. The off-season for travel is September.

Cheapest one-way flight priceINR 6,095
Cheapest return ticket priceINR 25,325
Cheapest monthSeptember
Peak season for travelJuly
Flight distance397.38 km

When is the cheapest time to book flights from Islip to Washington D.C.?

The cheapest time to fly from Islip to Washington D.C.: Jan 4 to Jan 11 — one-way prices start at INR 6,094.

Cheapest flights
From price
Search
  • 714
  • 1421
  • 2128

  • Jan

    284
  • 411
  • 1118
  • 1825

  • Feb

    251
  • 18
  • 815
  • 1522

  • Mar

    221
Displayed prices are calculated based on the cheapest average weekly prices of the corresponding route on Trip.com.

Frequently Asked Questions

  • What are the cheapest flights from Islip to Washington D.C. (ISP-WAS)?

    Based on Trip.com data, Frontier Airlines offers one-way fares as low as INR 6,095 on Cheapest nonstop routes (e.g. ISP to IAD on Sat, Jan 10), while Frontier Airlines offers Cheapest nonstop round-trips from INR 25,325 departing on Sat, Dec 13 and returning on Mon, Dec 15.
  • By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from Islip to Washington D.C. is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.
  • To find best deals on flights from Islip to Washington D.C., you can use various tools on Trip.com:
    · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Sat, Jan 10, with one-way flights priced at just INR 6,095.
    · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Frontier Airlines.
    · Set up price alerts to easily monitor ticket prices without having to check every day.
    · Check Trip.com flight deals and promo codes frequently.
    · Avoid peak season unless you book very early. It seems the peak season for Washington D.C. travel is around July.
    · Get exclusive promo codes for Trip.com app users.
  • The cheapest months to fly from Islip to Washington D.C. is September, when demand for travel is lower.
  • After crunching the numbers on our December flight calendar, it's currently cheapest to fly from Islip to Washington D.C. on December 13, 2025 with Frontier Airlines, with prices starting at INR 25,324.
  • The time difference between Washington D.C. and Islip is 0h.
  • Tickets can only be changed or canceled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.

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