Cheap Flights to St. Mary's County | Popular Routes to St. Mary's County from HK$509

View HK$509 flight on Wed, 8 Apr 2026Opens in a new window

Popular airlines to St. Mary's County

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  • Spirit Airlines

  • Southwest Airlines

  • United

  • Alaska Airlines

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Cheap round-trip flights to St. Mary's County

Prices were available within the past 7 days and start at HK$509 for one-way flights and HK$1,018 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Thu, 26 Mar - Wed, 1 Apr
JFK
New York
DCA
Washington
HK$1,018 Return, found 4 days ago
HK$1,018
Return
found 4 days ago
Select Delta flight, departing Thu, 26 Mar from New York to Washington, returning Wed, 1 Apr, priced at HK$1,018 found 4 days ago
Delta
Tue, 15 Sept - Fri, 18 Sept
LGA
New York
DCA
Washington
HK$1,470 Return, found 1 day ago
HK$1,470
Return
found 1 day ago
Select Delta flight, departing Tue, 15 Sept from New York to Washington, returning Fri, 18 Sept, priced at HK$1,470 found 1 day ago
Air Canada
Fri, 6 Mar - Sun, 8 Mar
YYZ
Toronto
DCA
Washington
HK$1,984 Return, found 5 days ago
HK$1,984
Return
found 5 days ago
Select Air Canada flight, departing Fri, 6 Mar from Toronto to Washington, returning Sun, 8 Mar, priced at HK$1,984 found 5 days ago
Alaska Airlines
Wed, 11 Mar - Tue, 24 Mar
LAX
Los Angeles
DCA
Washington
HK$2,013 Return, found 6 days ago
HK$2,013
Return
found 6 days ago
Select Alaska Airlines flight, departing Wed, 11 Mar from Los Angeles to Washington, returning Tue, 24 Mar, priced at HK$2,013 found 6 days ago
Air Canada
Fri, 6 Mar - Sun, 8 Mar
YTZ
Toronto
DCA
Washington
HK$2,046 Return, found 5 days ago
HK$2,046
Return
found 5 days ago
Select Air Canada flight, departing Fri, 6 Mar from Toronto to Washington, returning Sun, 8 Mar, priced at HK$2,046 found 5 days ago
Air Canada
Mon, 2 Mar - Mon, 9 Mar
YKF
Kitchener
DCA
Washington
HK$2,090 Return, found 6 days ago
HK$2,090
Return
found 6 days ago
Select Air Canada flight, departing Mon, 2 Mar from Kitchener to Washington, returning Mon, 9 Mar, priced at HK$2,090 found 6 days ago
United
Wed, 25 Feb - Thu, 26 Feb
EWR
New York
DCA
Washington
HK$4,985 Return, found 17 hours ago
HK$4,985
Return
found 17 hours ago
Select United flight, departing Wed, 25 Feb from New York to Washington, returning Thu, 26 Feb, priced at HK$4,985 found 17 hours ago
Air Canada
Thu, 26 Feb - Mon, 2 Mar
LHR
London
DCA
Washington
HK$5,190 Return, found 1 day ago
HK$5,190
Return
found 1 day ago
Select Air Canada flight, departing Thu, 26 Feb from London to Washington, returning Mon, 2 Mar, priced at HK$5,190 found 1 day ago
American Airlines
Sat, 7 Mar - Sat, 14 Mar
CLD
Carlsbad
DCA
Washington
HK$6,668 Return, found 4 days ago
HK$6,668
Return
found 4 days ago
Select American Airlines flight, departing Sat, 7 Mar from Carlsbad to Washington, returning Sat, 14 Mar, priced at HK$6,668 found 4 days ago
United
Fri, 27 Feb - Tue, 3 Mar
TPE
Taipei
DCA
Washington
HK$7,249 Return, found 1 day ago
HK$7,249
Return
found 1 day ago
Select United flight, departing Fri, 27 Feb from Taipei to Washington, returning Tue, 3 Mar, priced at HK$7,249 found 1 day ago

About St. Mary's County

Expedia offers flights to St. Mary's County to meet every traveller's needs. Whatever your flight need - Expedia has the flight for you. So choose from flights to St. Mary's County or destinations around the world and discover how easy it is to make your flight reservations on Expedia.

Frequently asked questions

How do I find cheap flights to St. Marys County that have flexible change policies?
It's as easy as can be with Expedia. Firstly, type in your travel details and click the "Search" button. Step 2? Check the "No change fee" box below the "Flexible change policies" filter on the top left of your screen. Step 3. Reserve your cheap and flexible airfare to St. Marys County.
Which airlines fly to St. Marys County?
A variety of airlines fly to destinations in or near St. Marys County. Your next big adventure is a few clicks away with these popular carriers:

  • American Airlines - 7,501 flights to or near St. Marys County each month, including 7,284 flights to Ronald Reagan Washington National Airport (DCA) and 216 flights to Washington Dulles Intl. Airport (IAD) per month.
  • United Airlines - 5,939 flights to or near St. Marys County each month, including 5,146 flights to Washington Dulles Intl. Airport (IAD) and 793 flights to Ronald Reagan Washington National Airport (DCA) per month.
  • Delta Air Lines - 2,036 flights to or near St. Marys County each month, including 1,516 flights to Ronald Reagan Washington National Airport (DCA) and 520 flights to Washington Dulles Intl. Airport (IAD) per month.

How can I find cheap tickets to St. Marys County?
You'll always score an epic deal with Expedia, but our "flexible dates" feature makes it even easier. Enter your preferred flight date, then click on the flexible dates link above to see the cheapest prices for nearby days. HK$1,018 was the lowest price for a flight to St. Marys County in the last seven days.
How much is a flight to St. Marys County?
If you were flying one way from New York (JFK), you could've picked up a low-cost fare for HK$509 in the last seven days. Round-trip flights to St. Marys County ranged from HK$1,018 to HK$7,609 during this same period.
What are the most popular airports to fly into in St. Marys County?
Pack your suitcase and touch down at one of these leading St. Marys County airports:

  • Ronald Reagan Washington National Airport (DCA) - 11,555 flights per month.
  • Washington Dulles Intl. Airport (IAD) - 6,533 flights per month.

When is the cheapest time to fly to St. Marys County?
Departing on a Tuesday, followed by a Monday, is generally the best way to get the cheapest deal. Stay away from the weekends if you can, because Saturday is typically the most expensive day. Spend the dollars you saved living it up in St. Marys County instead!
How much is a plane ticket to St. Marys County?
In the last seven days, fares to St. Marys County fluctuated from HK$1,018 to HK$7,609.
What is the best time to go to St. Marys County?
A nice time to visit St. Marys County, along with the exciting city of California, is over the lively months of May, July and September. Summer here begins June 20, and you can expect temperatures of between 21ºC and 27ºC if you visit then. This warmer weather is perfect for wandering around this city's attractions.
What months are the cheapest to book a flight to St. Marys County?
To grab an awesome deal to St. Marys County, try to book sometime in February when airfares are at their lowest. When's the most expensive time? In the United States, it's the month of December.

Trending flights to St. Mary's County

These prices were available within the past 7 days. Prices quoted are per person, return, for the period specified. Prices and availability are subject to change. Additional terms apply.

Air Canada
Mon, 9 Mar - Mon, 23 Mar
HKG
Hong Kong SAR
DCA
Washington
HK$7,609 Return, found 4 days ago
HK$7,609
Return
found 4 days ago
Select Air Canada flight, departing Mon, 9 Mar from Hong Kong SAR to Washington, returning Mon, 23 Mar, priced at HK$7,609 found 4 days ago
*Available to Expedia members.