Question 1

What is the cheapest month to book a flight from Islip, New York to Washington, D.C. Dulles Intl Airport?

Accepted Answer

Currently, August is the cheapest month in which you can book a flight from Islip, New York to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Islip, New York to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $346). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

Question 2

E

Accepted Answer

In terms of precipitation, rainfall in Washington, D.C. Dulles Intl Airport ranges from 2.6 - 4.0 inches per month. May is typically the wettest month, when rainfall can reach 4.0 in. February is typically the driest time to visit Washington, D.C. Dulles Intl Airport when rainfall is around 2.6 in.

Question 3

E

Accepted Answer

If weather is an important factor for your trip to Washington, D.C. Dulles Intl Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 35.6 F).

Question 4

How far in advance should I book a flight from Islip, New York to Washington, D.C. Dulles Intl Airport?

Accepted Answer

To save up to 171% on this flight, we recommend booking at least 32 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Islip, New York to Washington, D.C. Dulles Intl Airport from $298 1-2 weeks out and tickets from $451 for flights departing within the next 72 hours.

Question 5

What is the cheapest month to fly from Islip, New York to Washington, D.C. Dulles Intl Airport?

Accepted Answer

April is one of the best times of the year to fly to Washington, D.C. Dulles Intl Airport from Islip, New York. Prices for April average $235 per person but you can even find prices for as low as $91. The most expensive prices can be found in the month of December. Opting for a April flight can save you 26% on your journey compared to booking in December

Question 6

What is the cheapest time of day to fly from ISP to IAD?

Accepted Answer

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Islip, New York to Washington, D.C. Dulles Intl Airport as you normally would.

Question 7

What airport do you fly from for flights from Islip to Washington, D.C. Dulles Intl?

Accepted Answer

If you book a flight to Washington, D.C. Dulles Intl from Islip, you will be flying from Long Island, which is the city’s only airport. Islip Long Island (ISP) is located 7.2 mi from the center of Islip. There are 0 flights from Long Island to Washington, D.C. Dulles Intl per day from 0 different airlines.

Question 8

Can I find deals for flights from Islip to Dulles Intl that include hotel bookings?

Accepted Answer

Yes. In addition to deals on Islip to Dulles Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

Question 9

How can I find direct flights from Islip to Dulles Intl?

Accepted Answer

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Islip to Dulles Intl.

Question 10

Can I find deals for business class flights from Islip to Dulles Intl?

Accepted Answer

Yes. Cheapflights offers flight deals from Islip to Dulles Intl by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

Popular in	December
Cheapest in	April
Average price	$253

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Everything you need to know about your flight from Islip to Washington, D.C. Dulles Intl Airport

What is the cheapest month to book a flight from Islip, New York to Washington, D.C. Dulles Intl Airport?

Related info for your journey

Find useful and relevant information for your journey from Islip to Dulles Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly from for flights from Islip to Washington, D.C. Dulles Intl?

Can I find deals for flights from Islip to Dulles Intl that include hotel bookings?

How can I find direct flights from Islip to Dulles Intl?

Can I find deals for business class flights from Islip to Dulles Intl?

What is the cheapest month to book a flight from Islip, New York to Washington, D.C. Dulles Intl Airport?

Traveling to a place near Islip?

Browse thousands of different options on Cheapflights for your next trip

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Islip and Dulles Intl flights

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Cheap flights from Islip, NY (ISP) to Dulles Intl (IAD)

Find cheap flights from Islip to Dulles Intl with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Islip to Dulles Intl

Popular in

Cheapest in

Average price

Best time to book a flight from Islip to Dulles Intl

Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Islip with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Islip to Washington, D.C. Dulles Intl Airport

What is the cheapest month to book a flight from Islip, New York to Washington, D.C. Dulles Intl Airport?

Related info for your journey

Find useful and relevant information for your journey from Islip to Dulles Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly from for flights from Islip to Washington, D.C. Dulles Intl?

Can I find deals for flights from Islip to Dulles Intl that include hotel bookings?

How can I find direct flights from Islip to Dulles Intl?

Can I find deals for business class flights from Islip to Dulles Intl?

What is the cheapest month to book a flight from Islip, New York to Washington, D.C. Dulles Intl Airport?

Traveling to a place near Islip?

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Islip to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.

100% Free

Book with Flexibility

Travel Smart