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Dulles Intl

$72+ Cheap flights from Key Largo, FL to Dulles Intl (IAD)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 5/11. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — IAD
Apr 27 — May 41
Mon 4/27
Mon 5/4
1 adult, Economy
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Cheapflights Tip: The best prices from Key Largo to Washington, D.C. Dulles Intl are usually found in November or January, booked 20 days in advance, depart on a Friday or Thursday and return on a Monday

Cheap flight deals from Key Largo to Dulles Intl

Cheapest flights from Key Largo to Dulles Intl
Explore the most affordable flight options available from Key Largo to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 28, 2026.

This Frontier deal was found by Cheapflights users on 3/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/87:12 pm
MIA
-
IAD
1 stop5h 24m
Frontier
Thu 4/910:13 pm
IAD
-
MIA
Nonstop3h 01m
Frontier
Deal found 3/24$134
This eDestinos deal was found by Cheapflights users on 3/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/255:05 am
MIA
-
IAD
1 stop19h 31m
Frontier
Sat 5/210:51 am
IAD
-
MIA
1 stop23h 21m
Frontier
Deal found 3/26$135
This Frontier deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/96:33 pm
MIA
-
IAD
Nonstop2h 45m
Frontier
Mon 4/136:15 am
IAD
-
MIA
1 stop12h 02m
Frontier
Deal found 3/25$136
This Kiwi.com deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/145:22 pm
MIA
-
IAD
1 stop5h 47m
Frontier
Mon 5/1811:12 am
IAD
-
MIA
1 stop5h 15m
Frontier
Deal found 3/25$139
This Frontier deal was found by Cheapflights users on 3/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/88:10 am
MIA
-
IAD
1 stop9h 02m
Frontier
Sun 5/107:40 am
IAD
-
MIA
1 stop8h 47m
Frontier
Deal found 3/27$140
This Frontier deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/1612:26 pm
MIA
-
IAD
1 stop12h 10m
Frontier
Sun 4/196:20 am
IAD
-
MIA
1 stop11h 37m
Frontier
Deal found 3/25$141
This Super.com deal was found by Cheapflights users on 3/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/112:51 pm
MIA
-
IAD
Nonstop2h 45m
Frontier
Sun 4/1210:13 pm
IAD
-
MIA
Nonstop3h 01m
Frontier
Deal found 3/26$143
This Expedia deal was found by Cheapflights users on 3/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/85:05 am
MIA
-
IAD
1 stop9h 15m
Frontier
Sun 4/1210:13 pm
IAD
-
MIA
Nonstop3h 01m
Frontier
Deal found 3/26$144
This Frontier deal was found by Cheapflights users on 3/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/105:05 am
MIA
-
IAD
1 stop11h 44m
Frontier
Sun 4/1210:13 pm
IAD
-
MIA
Nonstop3h 01m
Frontier
Deal found 3/27$145

Find flight deals from Key Largo to Dulles Intl

Keep the following information in mind while searching for Key Largo to Dulles Intl flight deals. Data was last updated March 28, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$134
(Frontier)

One-way from

$72
(Trip.com)

Popular in

March

Cheapest in

November

Average price

$232
Provider with most accurate pricing for Miami-Washington, D.C. (WAS) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Miami-Washington, D.C. (WAS) flights.
Search Deals
From Key Largo to Washington, D.C. Dulles Intl
Search Deals
One-way flight from Key Largo to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 19% potential increase in price ($41 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Key Largo to Dulles Intl that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 28, 2026.
Use the filters below to find and compare flights from Key Largo to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Fri 4/17

6:00 pm-8:49 pm

Nonstop2h 49m

Washington, D.C. Dulles Intl

Sun 4/19

1:20 pm-4:16 pm

Nonstop2h 56m

$177

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Thu 5/14

4:50 pm-11:25 pm

1 stop6h 35m

Washington, D.C. Dulles Intl

Mon 5/18

8:40 am-11:36 am

Nonstop2h 56m

$187

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Thu 5/14

4:50 pm-11:25 pm

1 stop6h 35m

Washington, D.C. Dulles Intl

Sun 5/17

8:40 am-11:36 am

Nonstop2h 56m

$187

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Wed 7/15

2:09 pm-9:03 pm

1 stop6h 54m

Washington, D.C. Dulles Intl

Tue 7/21

7:21 pm-12:55 am

1 stop5h 34m

$197

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Sat 4/18

9:30 am-4:30 pm

1 stop7h 00m

Washington, D.C. Dulles Intl

Tue 4/21

8:35 am-11:31 am

Nonstop2h 56m

$216

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Sat 4/25

6:00 pm-8:49 pm

Nonstop2h 49m

Washington, D.C. Dulles Intl

Sat 5/2

1:20 pm-4:16 pm

Nonstop2h 56m

$257
Quickest round-trip

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Thu 4/23

1:20 pm-4:03 pm

Nonstop2h 43m

Washington, D.C. Dulles Intl

Tue 4/28

1:20 pm-4:16 pm

Nonstop2h 56m

$257

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Fri 5/22

5:22 pm-11:19 pm

1 stop5h 57m

Washington, D.C. Dulles Intl

Mon 5/25

8:45 am-11:35 am

Nonstop2h 50m

$257

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Fri 5/8

6:10 pm-9:00 pm

Nonstop2h 50m

Washington, D.C. Dulles Intl

Sun 5/10

1:20 pm-4:16 pm

Nonstop2h 56m

$257

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Thu 4/30

6:10 pm-9:00 pm

Nonstop2h 50m

Washington, D.C. Dulles Intl

Sun 5/3

1:20 pm-4:16 pm

Nonstop2h 56m

$257

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/25

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

Best time to book a flight from Key Largo to Dulles Intl

Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Key Largo with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

How far ahead should I book a flight from Key Largo to Washington, D.C. Dulles Intl Airport?

Use this chart to determine the optimal time to book a round-trip flight from Key Largo to Dulles Intl. Price data was last updated on March 13, 2026.

Booking 20 days in advance of your planned departure date is, on average, the best time to get cheap flights from Key Largo to Washington, D.C. Dulles Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Key Largo to Washington, D.C. Dulles Intl Airport?

Currently, December is the cheapest month in which you can book a flight from Key Largo to Washington, D.C. Dulles Intl Airport (average of $29). Flying from Key Largo to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $116). 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.

What is the cheapest time of day to fly from KE9 to IAD?

Find hourly flight availability from Key Largo to Dulles Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 28, 2026.

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

How much does it cost to fly round-trip from Key Largo to Washington, D.C. Dulles Intl Airport?

Reviews of airlines servicing Dulles Intl

Get insights into the airlines that provide service to Dulles Intl. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Dulles Intl. Reviews last updated March 28, 2026.
Read through reviews of airlines operating flights from Key Largo to Washington, D.C. Dulles Intl Airport, such as United Airlines,American Airlines, andFrontier. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,503 reviews

Food

6.6

Crew

8.1

Entertainment

7.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
United Airlines
7.4
Good
9,503 reviews
United Airlines
7.4
Good
9,503 reviews

Food

6.6

Crew

8.1

Entertainment

7.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
American Airlines
7.1
Good
11,519 reviews
United Airlines
7.4
Good
9,503 reviews

Food

6.6

Crew

8.1

Entertainment

7.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
Frontier
5.7
Fair
3,013 reviews
United Airlines
7.4
Good
9,503 reviews

Food

6.6

Crew

8.1

Entertainment

7.1

Overall

7.4

Comfort

7.3

Boarding

7.7

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family

Related info for your journey

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

  • How long is the flight from Key Largo to Washington, D.C. Dulles Intl Airport?

    Departing from Key Largo to Washington, D.C. Dulles Intl Airport will take you 2h 49m. Airlines will cover a distance of 923 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Key Largo to Washington, D.C. Dulles Intl Airport one-way?

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $35. Spirit Airlines flights start at $46 while deals on United Airlines start at $83 one-way.

  • What are the most reliable airlines from Key Largo to Washington, D.C. Dulles Intl Airport?

    No one likes to see their flight delayed. When booking a flight from Key Largo to Washington, D.C. Dulles Intl Airport consider choosing Volaris (92%), Frontier (79%) or United Airlines (75%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Key Largo to Washington, D.C. Dulles Intl Airport?

    While on average a flight from Key Largo to Washington, D.C. Dulles Intl Airport is generally $841, our data shows the cheapest flight currently is $75. When looking at the most popular route, (Miami - Washington, D.C. Dulles Intl), you can expect to pay $128 for that flight.

  • Can I find deals for flights from Key Largo to Dulles Intl that include hotel bookings?

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

  • How can I find direct flights from Key Largo to Dulles Intl?

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

  • Can I find deals for business class flights from Key Largo to Dulles Intl?

    Yes. Cheapflights offers flight deals from Key Largo 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.

  • What is the cheapest month to book a flight from Key Largo to Washington, D.C. Dulles Intl Airport?

    Currently, December is the cheapest month in which you can book a flight from Key Largo to Washington, D.C. Dulles Intl Airport (average of $29). Flying from Key Largo to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $116). 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.

See more FAQs

Traveling to a place near Washington, D.C. Dulles Intl Airport?

Book flights to Washington, D.C. Dulles Intl Airport if you plan to visit one of these locations
Alexandria
Woodbridge
Tysons
Owings Mills
Arlington
Springfield
Silver Spring
Herndon
Hyattsville
Hanover
Laurel
Rockville
Upper Marlboro
Fredericksburg
Largo
Bowie
Clinton
Towson
College Park
Cordova

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Key Largo to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Valparaiso to Dulles Intl flights
Daytona Beach to Reagan-National flights
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Key West to Baltimore flights
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Key West to Reagan-National flights
Daytona Beach to Baltimore flights
Gainesville to Baltimore flights
Gainesville to Reagan-National flights
Gainesville to Dulles Intl flights
Valdosta to Dulles Intl flights
Valdosta to Baltimore flights

Top 6 airlines flying from Key Largo to Dulles Intl

Discover the top 6 airlines that operate flights from Key Largo to Dulles Intl. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 28, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$29Average$139FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$31Average$115FlexibilityNo cancel feeOn-time65%
JetBlueCheapest$85Average$147FlexibilityNo cancel feeOn-time62%
DeltaCheapest$103Average$248FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$117Average$244FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$250Average$286FlexibilityNo cancel feeOn-time71%

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