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Grassy Key

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Grassy Key Flights as Low as $126

Prices found within past 7 days. Prices and availability subject to change. Additional terms may apply.

Frontier Airlines
Wed, Aug 5 - Tue, Aug 25
PHL
Philadelphia Intl.
MIA
Miami Intl.
$126 Roundtrip, found 2 days ago
$126
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Wed, Aug 5 from Philadelphia Intl. to Miami Intl., returning Tue, Aug 25, priced at $126 found 2 days ago
Frontier Airlines
Wed, Aug 19 - Thu, Sep 10
PHL
Philadelphia Intl.
MIA
Miami Intl.
$127 Roundtrip, found 23 hours ago
$127
Roundtrip
found 23 hours ago
Select Frontier Airlines flight, departing Wed, Aug 19 from Philadelphia Intl. to Miami Intl., returning Thu, Sep 10, priced at $127 found 23 hours ago
Frontier Airlines
Wed, Jun 24 - Thu, Jul 9
PHL
Philadelphia Intl.
MIA
Miami Intl.
$131 Roundtrip, found 2 days ago
$131
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Wed, Jun 24 from Philadelphia Intl. to Miami Intl., returning Thu, Jul 9, priced at $131 found 2 days ago
United
Sat, Sep 12 - Sat, Sep 19
EWR
Newark Liberty Intl. Airport
MIA
Miami Intl.
$177 Roundtrip, found 10 hours ago
$177
Roundtrip
found 10 hours ago
Select United flight, departing Sat, Sep 12 from Newark Liberty Intl. Airport to Miami Intl., returning Sat, Sep 19, priced at $177 found 10 hours ago
American Airlines
Sat, Sep 12 - Sat, Sep 19
EWR
Newark Liberty Intl. Airport
MIA
Miami Intl.
$177 Roundtrip, found 10 hours ago
$177
Roundtrip
found 10 hours ago
Select American Airlines flight, departing Sat, Sep 12 from Newark Liberty Intl. Airport to Miami Intl., returning Sat, Sep 19, priced at $177 found 10 hours ago
Delta
Sun, Sep 6 - Wed, Sep 23
EWR
Newark Liberty Intl. Airport
MIA
Miami Intl.
$202 Roundtrip, found 1 day ago
$202
Roundtrip
found 1 day ago
Select Delta flight, departing Sun, Sep 6 from Newark Liberty Intl. Airport to Miami Intl., returning Wed, Sep 23, priced at $202 found 1 day ago
Frontier Airlines
Wed, Aug 19 - Wed, Aug 26
STL
Lambert-St. Louis Intl.
MIA
Miami Intl.
$220 Roundtrip, found 1 day ago
$220
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Wed, Aug 19 from Lambert-St. Louis Intl. to Miami Intl., returning Wed, Aug 26, priced at $220 found 1 day ago
American Airlines
Wed, Jul 1 - Tue, Jul 14
STL
Lambert-St. Louis Intl.
EYW
Key West Intl.
$293 Roundtrip, found 21 hours ago
$293
Roundtrip
found 21 hours ago
Select American Airlines flight, departing Wed, Jul 1 from Lambert-St. Louis Intl. to Key West Intl., returning Tue, Jul 14, priced at $293 found 21 hours ago
American Airlines
Tue, Sep 15 - Sat, Sep 19
EWR
Newark Liberty Intl. Airport
EYW
Key West Intl.
$309 Roundtrip, just found
$309
Roundtrip
just found
Select American Airlines flight, departing Tue, Sep 15 from Newark Liberty Intl. Airport to Key West Intl., returning Sat, Sep 19, priced at $309 just found
American Airlines
Wed, Aug 5 - Tue, Aug 25
TTN
Mercer
MIA
Miami Intl.
$334 Roundtrip, found 2 days ago
$334
Roundtrip
found 2 days ago
Select American Airlines flight, departing Wed, Aug 5 from Mercer to Miami Intl., returning Tue, Aug 25, priced at $334 found 2 days ago
JetBlue Airways
Sat, Aug 29 - Fri, Sep 11
EWR
Newark Liberty Intl. Airport
EKW
Miami Central Brightline Train Station
$360 Roundtrip, found 6 days ago
$360
Roundtrip
found 6 days ago
Select JetBlue Airways flight, departing Sat, Aug 29 from Newark Liberty Intl. Airport to Miami Central Brightline Train Station, returning Fri, Sep 11, priced at $360 found 6 days ago
JetBlue Airways
Wed, Sep 9 - Tue, Sep 15
EWR
Newark Liberty Intl. Airport
AVT
Aventura Brightline Train Station
$372 Roundtrip, found 1 hour ago
$372
Roundtrip
found 1 hour ago
Select JetBlue Airways flight, departing Wed, Sep 9 from Newark Liberty Intl. Airport to Aventura Brightline Train Station, returning Tue, Sep 15, priced at $372 found 1 hour ago
JetBlue Airways
Wed, Aug 5 - Tue, Aug 25
PHL
Philadelphia Intl.
AVT
Aventura Brightline Train Station
$431 Roundtrip, found 2 days ago
$431
Roundtrip
found 2 days ago
Select JetBlue Airways flight, departing Wed, Aug 5 from Philadelphia Intl. to Aventura Brightline Train Station, returning Tue, Aug 25, priced at $431 found 2 days ago
JetBlue Airways
Wed, Aug 5 - Tue, Aug 25
PHL
Philadelphia Intl.
EKW
Miami Central Brightline Train Station
$431 Roundtrip, found 2 days ago
$431
Roundtrip
found 2 days ago
Select JetBlue Airways flight, departing Wed, Aug 5 from Philadelphia Intl. to Miami Central Brightline Train Station, returning Tue, Aug 25, priced at $431 found 2 days ago
American Airlines
Tue, Jun 30 - Tue, Jul 14
PHL
Philadelphia Intl.
EYW
Key West Intl.
$443 Roundtrip, found 5 days ago
$443
Roundtrip
found 5 days ago
Select American Airlines flight, departing Tue, Jun 30 from Philadelphia Intl. to Key West Intl., returning Tue, Jul 14, priced at $443 found 5 days ago
Alaska Airlines
Fri, Jul 17 - Mon, Jul 20
STL
Lambert-St. Louis Intl.
MIA
Miami Intl.
$1,014 Roundtrip, found 7 hours ago
$1,014
Roundtrip
found 7 hours ago
Select Alaska Airlines flight, departing Fri, Jul 17 from Lambert-St. Louis Intl. to Miami Intl., returning Mon, Jul 20, priced at $1,014 found 7 hours ago

Cheap Flights to Grassy Key

Fall in love at first flight with your vacation to Grassy Key by saving a ton of cash on your last-minute cheap flight. There’s no more scouring the internet for a good deal—book your flight to Grassy Key on Hotwire, and you’ll be up, up, and on a getaway in no time.

Because once the wheels are down in Grassy Key, the good times start rolling. So buckle up, you’re in for a fun ride.

Frequently Asked Questions About flights to Grassy Key

Don’t waste your time on endless searches for cheap airline tickets oneway or roundtrip. We’ll have you on your way to Grassy Key with a tiny bag of pretzels in your hand before you can say “tray tables in the upright position”—and for a ticket price that works for your vacay budget.

So all you have to worry about is where you’re headed after the MIA airport.

What is the cheapest month to fly to Grassy Key?

Airline ticket prices fluctuate all the time, depending on the day of the week or the month of the year. The cheapest round trip flights to Grassy Key are in August, but when you book your flight on Hotwire, savings are always in season.

How many airlines fly to Grassy Key?

Variety is the spice of life, even when it comes to booking your next trip. Want options for airlines? You’ll find 16 to choose from for your flight to Grassy Key.

What airport is best to fly into Grassy Key?

When you’re planning your trip to Grassy Key, convenience is the name of the game. Luckily, Grassy Key Florida Keys Marathon Airport is nearby so you can deplane and get going on checking off everything on your Grassy Key must-do list.

How much are flights to Grassy Key?

Got very cheap flights on your vacation itinerary? When you book your airline tickets to Grassy Key on Hotwire, you may just get what’s on your getaway wish list. With tickets as low as $126, you’ll have leftover cash for at least a magazine and a bottle of water at the airport book store.

How to get cheap flights to Grassy Key?

The trick to saving a stack of cash on your flight to Grassy Key? Snatch up that Hotwire flight deal when you see a killer rate because it could be gone in a flash. And with flights as low as $126 right now, why wait?

Grassy Key Flight Information
Destination airport
Miami Intl.
Destination airport IATA code
MIA
Roundtrip price
$126

Last Minute Hotel Deals in Grassy Key

Rainbow Bend Resort

Rainbow Bend Resort

2.5 out of 5
57784 Overseas Hwy Marathon FL
Book a stay at this beach hotel in Marathon. Enjoy a private beach, daily housekeeping, and a garden. Our guests praise the breakfast and the helpful staff in ...
8.2/10 Very Good! (996 reviews)
"Nice place. Staff were very helpful and friendly. Rooms are clean and comfortable. AC worked very well. Full breakfast provided 8am-10am with a limited menu. Kayaks and bikes available. Unfortunately there was a lot of seaweed on the water. Pool and hot tub worked but only accessible until 8pm. Parking ..."

Reviewed on Jun 13, 2026

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Rainbow Bend Resort
Gulf View Waterfront Resort

Gulf View Waterfront Resort

2.5 out of 5
58743 OVERSEAS HWY Marathon FL
Stay at this hotel in Marathon. Enjoy free WiFi, free parking, and daily housekeeping. Our guests praise the helpful staff and the clean rooms in our reviews. ...
8.4/10 Very Good! (583 reviews)
"Todo"

Reviewed on Jun 2, 2026

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Gulf View Waterfront Resort
Grassy Flats Resort & Beach Club

Grassy Flats Resort & Beach Club

4 out of 5
58182 Overseas Hwy Marathon FL
Stay at this hotel in Marathon. Enjoy free WiFi, free parking, and 2 outdoor pools. Our guests praise the helpful staff and the property condition in our reviews. ...
9.4/10 Exceptional! (457 reviews)
"The seaweed was horrible and the stink was really bad that was our only issue if it wasn’t for that would be close to 5 star and I know they can’t control nature"

Reviewed on Jun 13, 2026

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Grassy Flats Resort & Beach Club
Hawks Cay Resort

Hawks Cay Resort

4 out of 5
61 Hawks Cay Blvd Marathon FL
Book a stay at this luxury hotel in Marathon. Enjoy free WiFi, 3 outdoor pools, and a full-service spa. Our guests praise the pool and the helpful staff in our ...
8.2/10 Very Good! (1,016 reviews)
"The bathroom was odd very high bathtub to step into don't recommend for anyone elderly or not flexible. No separate shower was in high garden tub."

Reviewed on Jun 12, 2026

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Hawks Cay Resort
Isla Bella Beach Resort & Spa

Isla Bella Beach Resort & Spa

5 out of 5
1 Knights Key Boulevard Marathon FL
Book a stay at this luxury hotel in Marathon. Enjoy free WiFi, 5 outdoor pools, and a full-service spa. Our guests praise the pool and the helpful staff in our ...
9.2/10 Wonderful! (1,185 reviews)
"I’ve been to this resort several times and there’s a reason for that. This place has everything you need. Clean, spacious. Fun atmosphere for the families. Food was great at the restaurant. Great place I would recommend to anyone."

Reviewed on Jun 13, 2026

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Isla Bella Beach Resort & Spa
Lime Tree Bay Resort

Lime Tree Bay Resort

3.5 out of 5
68500 Overseas Hwy Long Key FL
Book a stay at this beach resort in Long Key. Enjoy free WiFi, free parking, and 3 outdoor pools. Our guests praise the pool and the helpful staff in our reviews. ...
9.2/10 Wonderful! (1,318 reviews)
"We had a wonderful stay and were thoroughly impressed with the property from start to finish. Our room was cozy, comfortable, and exceptionally clean, with a bed that made it easy to relax after a day in the sun. The amenities truly set this resort apart. We enjoyed having access to kayaking, snorkeling, ..."

Reviewed on Jun 13, 2026

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Lime Tree Bay Resort
Fairfield Inn & Suites by Marriott Marathon Florida Keys

Fairfield Inn & Suites by Marriott Marathon Florida Keys

3 out of 5
13201 Overseas Hwy Marathon FL
Book a stay at this business-friendly hotel in Marathon. Enjoy free breakfast, free WiFi, and 2 outdoor pools. Our guests praise the breakfast and the restaurant ...
9.2/10 Wonderful! (1,162 reviews)
"We absolutely loved Sparkys. Went there 3 nights for dinner. Great every time."

Reviewed on Jun 13, 2026

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Fairfield Inn & Suites by Marriott Marathon Florida Keys
Faro Blanco Resort Marathon Florida Keys, Curio by Hilton

Faro Blanco Resort Marathon Florida Keys, Curio by Hilton

4 out of 5
1996 Overseas Highway Marathon FL
Book a stay at this spa resort in Marathon. Enjoy free WiFi, 4 outdoor pools, and a full-service spa. Our guests praise the pool and the restaurant in our reviews. ...
8.6/10 Excellent! (1,162 reviews)
"Amazing location and super pet friendly!"

Reviewed on Jun 12, 2026

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Faro Blanco Resort Marathon Florida Keys, Curio by Hilton
See all 2,350 properties in Grassy Key
Lowest nightly price found within the past 24 hours based on a 1 night stay for 2 adults. Prices and availability subject to change. Additional terms may apply.