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Key Largo

$118+ 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 3/12. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — MIA
Jan 14 — Jan 211
Wed 1/14
Wed 1/21
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 October, booked 74 days in advance, depart on a Thursday or Wednesday and return on a Wednesday

Cheap 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 December 15, 2025.

This CheapOair deal was found by Cheapflights users on 12/12. 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.
Sat 12/1312:48 pmSEA - MIA
1 stop13h 31mFrontier
Sat 12/207:05 amMIA - SEA
1 stop30h 06mFrontier
Deal found 12/12$279
This Expedia deal was found by Cheapflights users on 12/12. 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.
Mon 12/159:45 amSEA - MIA
1 stop10h 33mFrontier
Thu 12/187:05 amMIA - SEA
1 stop30h 06mFrontier
Deal found 12/12$284
This CheapOair deal was found by Cheapflights users on 12/13. 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.
Mon 12/159:45 amSEA - MIA
1 stop10h 33mFrontier
Thu 12/257:05 amMIA - SEA
1 stop30h 06mFrontier
Deal found 12/13$305
This Priceline deal was found by Cheapflights users on 12/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/296:33 pmSEA - MIA
1 stop8h 02mFrontier
Thu 1/16:05 amMIA - SEA
1 stop9h 25mFrontier
Deal found 12/15$324
This CheapOair deal was found by Cheapflights users on 12/13. 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.
Mon 12/159:45 amSEA - MIA
1 stop10h 33mFrontier
Mon 12/227:05 amMIA - SEA
1 stop30h 06mFrontier
Deal found 12/13$325
This Frontier deal was found by Cheapflights users on 12/13. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:25 pmSEA - MIA
1 stop12h 35mFrontier
Tue 1/67:05 amMIA - SEA
1 stop13h 46mFrontier
Deal found 12/13$357
This Kiwi.com deal was found by Cheapflights users on 12/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/306:33 pmSEA - MIA
2 stops15h 33mMultiple Airlines
Tue 1/67:05 amMIA - SEA
1 stop13h 46mMultiple Airlines
Deal found 12/14$382
This Priceline deal was found by Cheapflights users on 12/14. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/306:33 pmSEA - MIA
1 stop8h 02mFrontier
Tue 1/67:05 amMIA - SEA
1 stop13h 46mFrontier
Deal found 12/14$387
This Trip.com deal was found by Cheapflights users on 12/12. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/226:33 pmSEA - MIA
1 stop8h 02mFrontier
Mon 1/55:30 amMIA - SEA
2 stops39h 21mFrontier
Deal found 12/12$392
This Kiwi.com deal was found by Cheapflights users on 12/15. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/286:28 pmSEA - MIA
1 stop13h 32mSun Country Air
Wed 12/3112:15 pmMIA - SEA
1 stop28h 06mSun Country Air
Deal found 12/15$396

Find 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 December 15, 2025.

Most accurate provider

Justfly.com
3 stars

Most trusted provider

Justfly.com
3 stars

Round-trip from

$201
(Kiwi.com)

One-way from

$118
(Expedia)

Popular in

December

Cheapest in

September

Average price

$579
Provider with most accurate pricing for Seattle/Tacoma Intl-Miami flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Miami flights.
Search Deals
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. 13% potential increase in price ($55 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($19 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

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 December 15, 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

Mon 1/12

5:40 pm-6:45 am

1 stop10h 05m

Miami

Wed 1/21

5:37 pm-9:35 pm

Nonstop6h 58m

$209

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Thu 1/29

7:00 pm-5:28 am

1 stop7h 28m

Miami

Thu 2/5

5:37 pm-9:35 pm

Nonstop6h 58m

$209

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Wed 1/28

7:35 am-4:27 pm

Nonstop5h 52m

Miami

Mon 2/2

7:50 am-2:54 pm

1 stop10h 04m

$209

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Mon 3/2

4:40 pm-5:28 am

1 stop9h 48m

Miami

Mon 3/9

5:57 pm-9:49 pm

Nonstop6h 52m

$209

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Fri 2/6

5:40 pm-6:40 am

1 stop10h 00m

Miami

Wed 2/11

5:37 pm-9:35 pm

Nonstop6h 58m

$209

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Mon 1/5

6:05 am-5:35 pm

1 stop8h 30m

Miami

Mon 1/12

5:37 pm-9:35 pm

Nonstop6h 58m

$209

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Mon 2/23

11:15 pm-10:21 am

1 stop8h 06m

Miami

Sat 2/28

7:50 am-2:44 pm

1 stop9h 54m

$219

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Fri 1/9

5:40 pm-6:45 am

1 stop10h 05m

Miami

Fri 1/16

8:00 am-4:58 pm

1 stop11h 58m

$219

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Mon 1/12

7:35 am-4:27 pm

Nonstop5h 52m

Miami

Tue 1/20

5:37 pm-9:35 pm

Nonstop6h 58m

$229

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Mon 3/9

8:00 am-4:47 pm

Nonstop5h 47m

$120

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/14

Showing 1-10 of 20 results
1
2

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 December 12, 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, February is the cheapest month in which you can book a flight from Seattle to Key Largo (average of $138). Flying from Seattle to Key Largo in December is currently the most expensive (average of $183). 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 December 15, 2025.

Unlike at noon, when flights are generally more expensive, you can save up to 52% on flights from Seattle to Key Largo by exploring options for tickets in the afternoon.

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. Friday 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 December 15, 2025.

The most flights from SEA to KE9 are scheduled on a Monday (8 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (2 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 December 15, 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
11,455 reviews

Entertainment

7.0

Food

7.1

Crew

8.5

Overall

8.0

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Alaska Airlines
8.0
Very good
11,455 reviews
Alaska Airlines
8.0
Very good
11,455 reviews

Entertainment

7.0

Food

7.1

Crew

8.5

Overall

8.0

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Delta
7.9
Good
8,008 reviews
Alaska Airlines
8.0
Very good
11,455 reviews

Entertainment

7.0

Food

7.1

Crew

8.5

Overall

8.0

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Hawaiian Airlines
7.8
Good
2,819 reviews
Alaska Airlines
8.0
Very good
11,455 reviews

Entertainment

7.0

Food

7.1

Crew

8.5

Overall

8.0

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
American Airlines
7.2
Good
11,048 reviews
Alaska Airlines
8.0
Very good
11,455 reviews

Entertainment

7.0

Food

7.1

Crew

8.5

Overall

8.0

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Frontier
5.8
Fair
3,081 reviews
Alaska Airlines
8.0
Very good
11,455 reviews

Entertainment

7.0

Food

7.1

Crew

8.5

Overall

8.0

Boarding

8.1

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.

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 33 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 10h 05m. There are 2719 mi between Seattle and Key Largo.

  • What are the cheapest airlines to fly from Seattle to Key Largo one-way?

    $96 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on Spirit Airlines and Hawaiian Airlines, with prices starting from $99 and $118, respectively.

  • 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 (90%), Delta (90%), American Airlines( 83%).

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

    The cheapest flight price from Seattle to Key Largo is $119. On average you can expect to pay $949. The most popular route, (Seattle/Tacoma Intl - Miami), can usually be booked for $199.

  • 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, February is the cheapest month in which you can book a flight from Seattle to Key Largo (average of $138). Flying from Seattle to Key Largo in December is currently the most expensive (average of $183). 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 December 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Hawaiian AirlinesCheapest$118Average$313FlexibilityNo cancel feeOn-time85%
Spirit AirlinesCheapest$128Average$266FlexibilityNo cancel feeOn-time65%
FrontierCheapest$133Average$301FlexibilityNo cancel feeOn-time62%
Sun Country AirCheapest$162Average$348FlexibilityNo cancel feeOn-time83%
DeltaCheapest$193Average$479FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$205Average$514FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$218Average$437FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$226Average$445FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$256Average$517FlexibilityNo cancel feeOn-time71%

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