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Key Largo

$139+ Cheap flights from Seattle (SEA) to Key Largo, FL

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 10/8. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — MIA
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Key Largo are usually found in September or August, booked 74 days in advance, depart on a Wednesday or Monday and return on a Wednesday

Cheap flight deals from Seattle to Key Largo

Keep the following information in mind while searching for Seattle to Key Largo flight deals. Data was last updated September 11, 2025.

Round-trip from

$187
(FlightHub)

One-way from

$139
(Delta)

Popular in

December

Cheapest in

September

Average price

$300
From Seattle/Tacoma Intl to Key Largo
Search Deals
One-way flight from Seattle/Tacoma Intl to Key Largo
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($37 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($15 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in September 2025
Search Deals

Find flight deals from Seattle to Key Largo

Cheapest flights from Seattle to Key Largo
Explore the most affordable flight options available from Seattle to Key Largo. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This FlightHub deal was found by Cheapflights users on 9/10. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/178:43 pmSEA - MIA
1 stop30h 36mFrontier
Sat 10/256:00 amMIA - SEA
1 stop9h 07mFrontier
Deal found 9/10$187
This Expedia deal was found by Cheapflights users on 9/9. 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.
Sat 11/812:58 pmSEA - MIA
1 stop14h 21mFrontier
Sat 11/156:00 amMIA - SEA
1 stop9h 13mFrontier
Deal found 9/9$188
This Booking.com deal was found by Cheapflights users on 9/10. 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.
Sat 10/188:43 pmSEA - MIA
1 stop30h 36mFrontier
Sun 10/266:00 amMIA - SEA
1 stop28h 33mFrontier
Deal found 9/10$194
This Frontier deal was found by Cheapflights users on 9/9. 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.
Sun 11/22:22 pmSEA - MIA
2 stops16h 49mFrontier
Fri 11/146:00 amMIA - SEA
1 stop9h 13mFrontier
Deal found 9/9$204
This Frontier deal was found by Cheapflights users on 9/9. 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 10/174:11 pmSEA - MIA
2 stops11h 08mFrontier
Thu 10/236:00 amMIA - SEA
1 stop9h 07mFrontier
Deal found 9/9$209
This Booking.com deal was found by Cheapflights users on 9/10. 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.
Fri 10/36:12 amSEA - MIA
1 stop15h 32mFrontier
Sun 10/56:00 amMIA - SEA
1 stop21h 30mFrontier
Deal found 9/10$210
This Frontier deal was found by Cheapflights users on 9/10. 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 10/301:18 pmSEA - MIA
1 stop14h 01mFrontier
Sun 11/210:32 pmMIA - SEA
2 stops17h 31mFrontier
Deal found 9/10$213
This Booking.com deal was found by Cheapflights users on 9/11. 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.
Fri 10/178:43 pmSEA - MIA
1 stop16h 31mFrontier
Mon 10/206:00 amMIA - SEA
1 stop9h 07mFrontier
Deal found 9/11$214
This Frontier deal was found by Cheapflights users on 9/10. 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 11/512:58 pmSEA - MIA
1 stop14h 21mFrontier
Mon 11/106:00 amMIA - SEA
1 stop9h 13mFrontier
Deal found 9/10$216
This American Airlines deal was found by Cheapflights users on 9/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/310:08 pmSEA - MIA
Nonstop5h 41mAmerican Airlines
Tue 11/117:35 pmMIA - SEA
Nonstop6h 51mAmerican Airlines
Deal found 9/11$217
This American Airlines deal was found by Cheapflights users on 9/10. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/68:49 pmSEA - MIA
Nonstop5h 41mAmerican Airlines
Tue 10/147:50 pmMIA - SEA
Nonstop6h 45mAmerican Airlines
Deal found 9/10$218
This Kiwi.com deal was found by Cheapflights users on 9/9. 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.
Fri 10/178:43 pmSEA - MIA
1 stop30h 36mFrontier
Mon 10/276:00 amMIA - SEA
1 stop9h 07mFrontier
Deal found 9/9$219

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Key Largo 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 11, 2025.
Use the filters below to find and compare flights from Seattle to Key Largo that are best for you.

Fly from

Seattle

Fly to

Key Largo

Route

Depart

Return

Price

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Wed 11/5

8:00 am-4:54 pm

Nonstop5h 54m

Miami

Wed 11/12

6:00 pm-9:53 pm

Nonstop6h 53m

$237

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Tue 10/14

8:30 am-5:29 pm

Nonstop5h 59m

Miami

Fri 10/24

6:43 pm-10:30 pm

Nonstop6h 47m

$237

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Thu 10/9

8:00 am-4:54 pm

Nonstop5h 54m

Miami

Wed 10/15

6:05 pm-9:47 pm

Nonstop6h 42m

$257

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Wed 10/1

8:25 am-5:45 pm

Nonstop6h 20m

Miami

Sat 10/4

6:43 pm-10:30 pm

Nonstop6h 47m

$257

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Fri 10/3

8:30 am-5:23 pm

Nonstop5h 53m

Miami

Thu 10/9

6:05 pm-9:47 pm

Nonstop6h 42m

$257

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Tue 9/30

8:25 am-5:45 pm

Nonstop6h 20m

Miami

Sat 10/4

6:43 pm-10:30 pm

Nonstop6h 47m

$257

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Fri 10/10

8:00 am-4:54 pm

Nonstop5h 54m

Miami

Wed 10/15

6:05 pm-9:47 pm

Nonstop6h 42m

$257

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Wed 11/12

7:55 am-4:49 pm

Nonstop5h 54m

Miami

Mon 11/17

6:00 pm-9:53 pm

Nonstop6h 53m

$257

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Sun 12/7

8:45 am-5:34 pm

Nonstop5h 49m

Miami

Thu 1/8

4:45 pm-10:24 pm

1 stop8h 39m

$267

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Sun 11/16

8:53 am-5:46 pm

Nonstop5h 53m

Miami

Tue 11/18

6:46 pm-10:30 pm

Nonstop6h 44m

$277

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

Showing 1-10 of 22 results
1
2
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Best time to book a flight from Seattle to Key Largo

Have a flexible travel schedule? Discover the best time to fly to Key Largo from Seattle 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 Seattle to Key Largo

How far ahead should I book a flight from Seattle to Key Largo?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Key Largo. Price data was last updated on August 29, 2025.

The price you pay for your flight from Seattle to Key Largo may vary depending on when you book. For the best chance of a lower fare, look to book 74 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Seattle to Key Largo?

Currently, September is the cheapest month in which you can book a flight from Seattle to Key Largo (average of $232). Flying from Seattle to Key Largo in March is currently the most expensive (average of $289). 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 SEA to KE9?

Find hourly flight availability from Seattle to Key Largo. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 11, 2025.

When flying from Seattle to Key Largo, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

What is the cheapest day to fly from Seattle to Key Largo?

Use this chart to determine the cheapest time to fly round-trip from Seattle to Key Largo. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Seattle to Key Largo flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Seattle to Key Largo

Explore weekly flight availability from Seattle to Key Largo. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated September 11, 2025.

The most flights from SEA to KE9 are scheduled on a Thursday (6 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (4 on average).

Reviews of airlines servicing Key Largo

Get insights into the airlines that provide service to Key Largo. 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 Key Largo. Reviews last updated September 11, 2025.
See what other customers who have flown with Alaska Airlines, Delta, and Hawaiian Airlines from Seattle to Key Largo have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.0

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.0

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Delta
8.0
Very good
7,960 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.0

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Hawaiian Airlines
7.8
Good
2,723 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.0

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.0

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Frontier
5.8
Fair
3,177 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Overall

8.0

Entertainment

7.0

Food

7.1

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Key Largo. 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 Seattle to Key Largo?

    Seattle/Tacoma Intl (SEA) is the airport you will fly out of if you book a flight from Seattle to Key Largo. You should not have trouble finding flights to Key Largo from Seattle/Tacoma Intl; the airport handles an average of 5 outbound flights to Key Largo per day. You should also have plenty of airline options to choose from since 9 airlines have flights from the Seattle airport to Key Largo. It is only a 11.4 mi journey to Seattle/Tacoma Intl (SEA) from Seattle’s city center.

  • How popular is this Seattle to Key Largo flight route?

    The Seattle/Tacoma Intl to Key Largo flight path was viewed by 42 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Seattle to Key Largo?

    Departing from Seattle to Key Largo will take you 5h 54m. There are 2719 mi between Seattle and Key Largo. All flights are typically nonstop.

  • What are the most reliable airlines from Seattle to Key Largo?

    Before booking your flight to Key Largo from Seattle, check out the most reliable airlines to get you to your destination on time: LATAM Airlines (71%), Delta (71%), American Airlines( 66%).

  • What are the cheapest flights from Seattle to Key Largo?

    The cheapest flight price from Seattle to Key Largo is $138. On average you can expect to pay $771. The most popular route, (Seattle/Tacoma Intl - Miami), can usually be booked for $213.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Seattle to Key Largo 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 Seattle to Key Largo?

    Currently, September is the cheapest month in which you can book a flight from Seattle to Key Largo (average of $232). Flying from Seattle to Key Largo in March is currently the most expensive (average of $289). 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.

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Top 9 airlines flying from Seattle to Key Largo

Discover the top 9 airlines that operate flights from Seattle to Key Largo. 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 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
Hawaiian AirlinesCheapest$118Average$315FlexibilityNo cancel feeOn-time85%
Spirit AirlinesCheapest$128Average$262FlexibilityNo cancel feeOn-time65%
FrontierCheapest$129Average$273FlexibilityNo cancel feeOn-time62%
Sun Country AirCheapest$162Average$348FlexibilityNo cancel feeOn-time83%
DeltaCheapest$186Average$492FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$205Average$501FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$208Average$457FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$237Average$484FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$246Average$520FlexibilityNo cancel feeOn-time71%

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