HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Key Largo

$120+ 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 2/19. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — MIA
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Seattle to Key Largo with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Key Largo are usually found in September or October, booked 83 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

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 October 30, 2025.

This Vliegwinkel deal was found by Cheapflights users on 10/28. 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 Vliegwinkel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/88:45 amSEA - MIA
Nonstop5h 49mMultiple Airlines
Tue 12/166:00 amMIA - SEA
1 stop11h 46mMultiple Airlines
Deal found 10/28$198
This Kiwi.com deal was found by Cheapflights users on 10/28. 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 11/142:22 pmSEA - MIA
1 stop12h 57mFrontier
Tue 11/183:06 pmMIA - SEA
2 stops24h 01mFrontier
Deal found 10/28$199
This CheapOair deal was found by Cheapflights users on 10/28. 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.
Wed 11/121:37 pmSEA - MIA
1 stop13h 42mFrontier
Mon 11/176:00 amMIA - SEA
1 stop9h 13mFrontier
Deal found 10/28$206
This Expedia deal was found by Cheapflights users on 10/30. 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 12/89:45 amSEA - MIA
1 stop10h 33mMultiple Airlines
Wed 12/176:34 pmMIA - SEA
Nonstop6h 56mMultiple Airlines
Deal found 10/30$207
This Kiwi.com deal was found by Cheapflights users on 10/28. 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.
Mon 11/249:15 pmSEA - MIA
Nonstop5h 42mHawaiian Airlines
Wed 12/36:34 pmMIA - SEA
Nonstop6h 56mHawaiian Airlines
Deal found 10/28$208
This Kiwi.com deal was found by Cheapflights users on 10/28. 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 11/181:37 pmSEA - MIA
2 stops19h 52mFrontier
Tue 11/257:12 amMIA - SEA
1 stop28h 10mFrontier
Deal found 10/28$209
This Frontier deal was found by Cheapflights users on 10/28. 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 11/121:37 pmSEA - MIA
1 stop13h 42mFrontier
Mon 11/246:15 amMIA - SEA
1 stop8h 41mFrontier
Deal found 10/28$211
This Trip.com deal was found by Cheapflights users on 10/28. 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 12/88:45 amSEA - MIA
Nonstop5h 49mHawaiian Airlines
Tue 12/166:34 pmMIA - SEA
Nonstop6h 56mHawaiian Airlines
Deal found 10/28$212
This Kiwi.com deal was found by Cheapflights users on 10/29. 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 11/142:22 pmSEA - MIA
1 stop12h 57mMultiple Airlines
Tue 11/255:02 pmMIA - SEA
2 stops23h 20mMultiple Airlines
Deal found 10/29$214
This Orbitz deal was found by Cheapflights users on 10/29. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/1512:58 pmSEA - MIA
1 stop14h 21mMultiple Airlines
Wed 11/196:46 pmMIA - SEA
Nonstop6h 44mMultiple Airlines
Deal found 10/29$215
This Kiwi.com deal was found by Cheapflights users on 10/28. 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 12/41:09 pmSEA - MIA
1 stop13h 10mFrontier
Sun 12/76:09 pmMIA - SEA
2 stops18h 57mFrontier
Deal found 10/28$216

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 October 30, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$197
(Cheapflightsfares)

One-way from

$120
(Delta)

Popular in

December

Cheapest in

September

Average price

$297
Provider with most accurate pricing for Seattle/Tacoma Intl-Miami flight deals.
Search Deals
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. 10% potential increase in price ($43 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($16 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 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 October 30, 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

Thu 2/19

8:00 am-5:05 pm

Nonstop6h 05m

Miami

Tue 2/24

6:05 pm-10:12 pm

Nonstop7h 07m

$199

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Tue 3/10

7:55 am-4:55 pm

Nonstop6h 00m

Miami

Wed 3/11

5:55 pm-9:25 pm

Nonstop6h 30m

$239

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Mon 3/9

8:00 am-5:05 pm

Nonstop6h 05m

Miami

Tue 3/10

6:05 pm-10:12 pm

Nonstop7h 07m

$239

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Sun 1/18

7:45 am-4:37 pm

Nonstop5h 52m

Miami

Wed 1/21

5:47 pm-9:45 pm

Nonstop6h 58m

$239

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Sun 3/1

8:00 am-5:05 pm

Nonstop6h 05m

Miami

Tue 3/3

6:05 pm-10:12 pm

Nonstop7h 07m

$240

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Sun 3/8

7:10 pm-5:50 am

1 stop7h 40m

Miami

Tue 3/10

7:45 am-4:14 pm

1 stop11h 29m

$259

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Wed 12/17

8:25 am-6:12 am

1 stop18h 47m

Miami

Wed 12/24

7:25 am-11:22 am

Nonstop6h 57m

$267

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Tue 3/3

7:55 am-4:55 pm

Nonstop6h 00m

Miami

Wed 3/4

4:45 pm-10:24 pm

1 stop8h 39m

$268

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Tue 12/16

7:55 am-4:50 pm

Nonstop5h 55m

Miami

Thu 1/8

5:47 pm-9:45 pm

Nonstop6h 58m

$278

SeattleMiami

SEA - MIA

SEAMIA

Seattle/Tacoma Intl

Sun 12/14

8:25 am-4:00 pm

1 stop28h 35m

Miami

Sun 12/21

7:25 am-11:22 am

Nonstop6h 57m

$292

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/30

Showing 1-10 of 21 results
1
2
3

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 October 24, 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 83 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, October is the cheapest month in which you can book a flight from Seattle to Key Largo (average of $133). 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 October 30, 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.

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 October 30, 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
11,210 reviews

Boarding

8.1

Food

7.1

Entertainment

7.0

Crew

8.5

Comfort

7.8

Overall

8.0

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
11,210 reviews
Alaska Airlines
8.0
Very good
11,210 reviews

Boarding

8.1

Food

7.1

Entertainment

7.0

Crew

8.5

Comfort

7.8

Overall

8.0

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
7,992 reviews
Alaska Airlines
8.0
Very good
11,210 reviews

Boarding

8.1

Food

7.1

Entertainment

7.0

Crew

8.5

Comfort

7.8

Overall

8.0

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
2,796 reviews
Alaska Airlines
8.0
Very good
11,210 reviews

Boarding

8.1

Food

7.1

Entertainment

7.0

Crew

8.5

Comfort

7.8

Overall

8.0

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
11,032 reviews
Alaska Airlines
8.0
Very good
11,210 reviews

Boarding

8.1

Food

7.1

Entertainment

7.0

Crew

8.5

Comfort

7.8

Overall

8.0

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
3,124 reviews
Alaska Airlines
8.0
Very good
11,210 reviews

Boarding

8.1

Food

7.1

Entertainment

7.0

Crew

8.5

Comfort

7.8

Overall

8.0

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 2 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 39 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 6h. There are 2719 mi between Seattle and Key Largo. All flights are typically nonstop.

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

    $120 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on Southwest and United Airlines, with prices starting from $125 and $130, 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: Alaska Airlines (87%), Hawaiian Airlines (87%), Air Tahiti Nui( 87%).

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

    The cheapest flight price from Seattle to Key Largo is $128. On average you can expect to pay $894. The most popular route, (Seattle/Tacoma Intl - Miami), can usually be booked for $165.

  • 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, October is the cheapest month in which you can book a flight from Seattle to Key Largo (average of $133). 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.

See more FAQs

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 Seattle to Key Largo

See prices for flight routes from nearby airports that may be better suited for you.
Seattle to Orlando flights
Seattle to Miami flights
Seattle to Tampa flights
Seattle to Fort Lauderdale flights
Portland to Orlando flights
Portland to Miami flights
Portland to Tampa flights
Portland to Fort Lauderdale flights
Seattle to Jacksonville flights
Seattle to Fort Myers flights
Seattle to West Palm Beach flights
Seattle to Pensacola flights
Seattle to Sarasota flights
Spokane to Orlando flights
Portland to Jacksonville flights
Spokane to Miami flights
Portland to Fort Myers flights
Portland to Pensacola flights
Portland to West Palm Beach flights
Seattle to Key West flights
Portland to Sarasota flights
Spokane to Tampa flights
Seattle to Valparaiso flights
Pasco to Orlando flights
Pasco to Tampa flights
Pasco to Miami flights
Seattle to Daytona Beach flights
Seattle to Panama City flights
Portland to Tallahassee flights
Spokane to Fort Lauderdale flights
Spokane to Pensacola flights
Seattle to Melbourne flights
Seattle to Gainesville flights
Portland to Daytona Beach flights
Portland to Gainesville flights
Spokane to Jacksonville flights
Pasco to Fort Lauderdale flights
Portland to Key West flights
Seattle to Tallahassee flights
Portland to Panama City flights
Spokane to Melbourne flights
Spokane to Sarasota flights
Spokane to Panama City flights
Pasco to Fort Myers flights
Bellingham to Miami flights
Portland to Melbourne flights
Spokane to Fort Myers flights
Portland to Valparaiso flights
Spokane to Key West flights
Spokane to Daytona Beach flights

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 October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
Hawaiian AirlinesCheapest$118Average$313FlexibilityNo cancel feeOn-time85%
Spirit AirlinesCheapest$128Average$258FlexibilityNo cancel feeOn-time65%
FrontierCheapest$128Average$286FlexibilityNo cancel feeOn-time62%
Sun Country AirCheapest$162Average$348FlexibilityNo cancel feeOn-time83%
DeltaCheapest$186Average$487FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$205Average$426FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$228Average$461FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$237Average$476FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$246Average$513FlexibilityNo cancel feeOn-time71%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.
Site
Cookie settings©2025 Cheapflights