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Dulles Intl

$59+ 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 10/15. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — IAD
Oct 16 — Oct 231
Thu 10/16
Thu 10/23
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 September or August, booked 65 days in advance, depart on a Friday or Thursday and return on a Thursday

Cheap 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 September 16, 2025.

Round-trip from

$98
(CheapOair)

One-way from

$59
(United Airlines)

Popular in

December

Cheapest in

September

Average price

$147
From Key Largo to Washington, D.C. Dulles Intl
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One-way flight from Key Largo to Washington, D.C. Dulles Intl
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Highest demand for flights based on searches. 20% potential increase in price ($58 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($10 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find 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 September 16, 2025.

This CheapOair deal was found by Cheapflights users on 9/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/211:35 amMIA - IAD
Nonstop2h 50mFrontier
Sun 10/53:15 pmIAD - MIA
Nonstop2h 49mFrontier
Deal found 9/13$98
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/311:35 amMIA - IAD
Nonstop2h 50mFrontier
Sun 10/53:15 pmIAD - MIA
Nonstop2h 49mFrontier
Deal found 9/15$99
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/2511:35 amMIA - IAD
Nonstop2h 50mFrontier
Mon 9/293:15 pmIAD - MIA
Nonstop2h 49mFrontier
Deal found 9/14$100
This Cheapflightsfares deal was found by Cheapflights users on 9/14. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/2611:35 amMIA - IAD
Nonstop2h 50mFrontier
Sun 9/283:15 pmIAD - MIA
Nonstop2h 49mFrontier
Deal found 9/14$101
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/2511:35 amMIA - IAD
Nonstop2h 50mFrontier
Sun 9/283:15 pmIAD - MIA
Nonstop2h 49mFrontier
Deal found 9/14$102
This Cheapflightsfares deal was found by Cheapflights users on 9/14. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/1411:31 amMIA - IAD
Nonstop2h 34mFrontier
Sun 11/163:51 pmIAD - MIA
Nonstop2h 47mFrontier
Deal found 9/14$103
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/612:32 pmMIA - IAD
Nonstop2h 34mFrontier
Mon 11/103:51 pmIAD - MIA
Nonstop2h 47mFrontier
Deal found 9/14$104
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/1011:34 amMIA - IAD
Nonstop2h 51mFrontier
Mon 10/133:10 pmIAD - MIA
Nonstop2h 47mFrontier
Deal found 9/15$105
This CheapOair deal was found by Cheapflights users on 9/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/911:34 amMIA - IAD
Nonstop2h 51mFrontier
Mon 10/133:10 pmIAD - MIA
Nonstop2h 47mFrontier
Deal found 9/13$106
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1811:35 amMIA - IAD
Nonstop2h 50mFrontier
Sun 9/213:15 pmIAD - MIA
Nonstop2h 49mFrontier
Deal found 9/14$107
This Booking.com deal was found by Cheapflights users on 9/16. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/2311:34 amMIA - IAD
Nonstop2h 51mFrontier
Mon 10/273:10 pmIAD - MIA
Nonstop2h 47mFrontier
Deal found 9/16$112
This Booking.com deal was found by Cheapflights users on 9/16. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/2311:34 amMIA - IAD
Nonstop2h 51mFrontier
Sun 10/263:10 pmIAD - MIA
Nonstop2h 47mFrontier
Deal found 9/16$113

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 September 16, 2025.
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

Key Largo

Fly to

Dulles Intl

Route

Depart

Return

Price

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Thu 10/30

12:51 pm-3:25 pm

Nonstop2h 34m

Washington, D.C. Dulles Intl

Tue 11/4

8:25 am-11:14 am

Nonstop2h 49m

$117

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Wed 10/15

1:15 pm-3:50 pm

Nonstop2h 35m

Washington, D.C. Dulles Intl

Sat 10/18

8:25 am-11:16 am

Nonstop2h 51m

$133

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Fri 10/10

1:15 pm-3:50 pm

Nonstop2h 35m

Washington, D.C. Dulles Intl

Sun 10/12

8:25 am-11:16 am

Nonstop2h 51m

$142

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Wed 10/1

1:28 pm-9:11 pm

1 stop7h 43m

Washington, D.C. Dulles Intl

Sun 10/12

8:25 am-11:16 am

Nonstop2h 51m

$152

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Fri 10/24

1:28 pm-9:11 pm

1 stop7h 43m

Washington, D.C. Dulles Intl

Mon 10/27

8:45 am-2:37 pm

1 stop5h 52m

$157

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Fri 1/23

6:25 pm-9:11 pm

Nonstop2h 46m

Washington, D.C. Dulles Intl

Tue 2/3

8:15 am-11:16 am

Nonstop3h 01m

$159

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Thu 10/9

1:15 pm-3:50 pm

Nonstop2h 35m

Washington, D.C. Dulles Intl

Tue 10/14

8:25 am-11:16 am

Nonstop2h 51m

$187

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Thu 10/2

1:15 pm-3:50 pm

Nonstop2h 35m

Washington, D.C. Dulles Intl

Sat 10/4

8:25 am-11:16 am

Nonstop2h 51m

$187

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Wed 10/1

1:15 pm-3:50 pm

Nonstop2h 35m

Washington, D.C. Dulles Intl

Fri 10/3

8:25 am-11:16 am

Nonstop2h 51m

$187

MiamiWashington, D.C.

MIA - IAD

MIAIAD

Miami

Tue 12/16

12:50 pm-3:24 pm

Nonstop2h 34m

$69

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 19 results
1
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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 September 12, 2025.

Booking 65 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, August is the cheapest month in which you can book a flight from Key Largo to Washington, D.C. Dulles Intl Airport (average of $292). Flying from Key Largo to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $337). 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 September 16, 2025.

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.

What is the cheapest day to fly from Key Largo to Washington, D.C. Dulles Intl Airport?

Use this chart to determine the cheapest time to fly round-trip from Key Largo to Dulles Intl. Price data was last updated on February 16, 2025.

Travelers seeking maximum savings on their Key Largo to Washington, D.C. Dulles Intl Airport flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

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 September 16, 2025.
Read through reviews of airlines operating flights from Key Largo to Washington, D.C. Dulles Intl Airport, such as Delta, United Airlines, and American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,957 reviews

Entertainment

7.9

Crew

8.5

Boarding

8.2

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.
Delta
8.0
Very good
7,957 reviews
Delta
8.0
Very good
7,957 reviews

Entertainment

7.9

Crew

8.5

Boarding

8.2

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.
United Airlines
7.4
Good
8,924 reviews
Delta
8.0
Very good
7,957 reviews

Entertainment

7.9

Crew

8.5

Boarding

8.2

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,957 reviews

Entertainment

7.9

Crew

8.5

Boarding

8.2

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.
Spirit Airlines
6.3
Okay
8,019 reviews
Delta
8.0
Very good
7,957 reviews

Entertainment

7.9

Crew

8.5

Boarding

8.2

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.
Frontier
5.8
Fair
3,174 reviews
Delta
8.0
Very good
7,957 reviews

Entertainment

7.9

Crew

8.5

Boarding

8.2

Food

7.3

Comfort

7.9

Overall

8.0

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.

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 34m. Airlines will cover a distance of 923 mi. Generally, flights for this route are nonstop.

  • 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 Copa Airlines (85%), United Airlines (85%) or Frontier (62%) 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 $163, our data shows the cheapest flight currently is $39. When looking at the most popular route, (Miami - Washington, D.C. Dulles Intl), you can expect to pay $92 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, August is the cheapest month in which you can book a flight from Key Largo to Washington, D.C. Dulles Intl Airport (average of $292). Flying from Key Largo to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $337). 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
Woodbridge
Arlington
Alexandria
Tysons
Silver Spring
Springfield
Gaithersburg
Fredericksburg
Linthicum Heights
Fairfax
Falls Church
Owings Mills
Manassas
Rockville
Hanover
Oxon Hill
Laurel
Towson
National Harbor
Dundalk

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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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 September 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$37Average$141FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$96Average$146FlexibilityNo cancel feeOn-time65%
DeltaCheapest$108Average$229FlexibilityNo cancel feeOn-timeN/A
JetBlueCheapest$120Average$217FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$137Average$274FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$250Average$343FlexibilityNo cancel feeOn-time71%

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