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$354+ Cheap flights from Boston to Sidney, MT (BOS - SDY)

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 8/24. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — SDY
Aug 27 — Sep 31
Thu 8/27
Thu 9/3
1 adult, Economy
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Cheap flight deals from Boston to Sidney

Cheapest flights from Boston to Sidney
Explore the most affordable flight options available from Boston to Sidney. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 28, 2026.

This United deal was found by Cheapflights users on 7/23. 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 United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/228:25 am
BOS
-
SDY
3 stops37h 23m
Multiple Airlines
Sat 8/297:35 am
SDY
-
BOS
2 stops14h 15m
Multiple Airlines
Deal found 7/23$820
This Expedia deal was found by Cheapflights users on 7/24. 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.
Fri 8/213:31 pm
BOS
-
SDY
2 stops18h 41m
Multiple Airlines
Fri 8/289:45 am
SDY
-
BOS
2 stops18h 24m
Multiple Airlines
Deal found 7/24$1,055

Find flight deals from Boston to Sidney

Discover tips and strategies to find the most affordable flight options for your journey from Boston (BOS) to Sidney (SDY). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated July 28, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$820
(United)

One-way from

$354
(Expedia)
Provider with most accurate pricing for Boston Logan Intl-Sidney Richland Municipal flight deals.
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Provider most trusted by Cheapflights users for Boston Logan Intl-Sidney Richland Municipal flights.
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From Boston Logan Intl to Sidney Richland Municipal
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One-way flight from Boston Logan Intl to Sidney Richland Municipal
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Boston to Sidney 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 July 28, 2026.
Use the filters below to find and compare flights from Boston to Sidney that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

BostonSidney

BOS - SDY

BOSSDY

Boston Logan Intl

Sat 8/22

8:25 am-7:48 pm

3 stops37h 23m

Sidney Richland Municipal

Sat 8/29

7:35 am-11:50 pm

2 stops14h 15m

$820
Quickest round-trip

BostonSidney

BOS - SDY

BOSSDY

Boston Logan Intl

Fri 8/21

3:31 pm-8:12 am

2 stops18h 41m

Sidney Richland Municipal

Fri 8/28

9:45 am-6:09 am

2 stops18h 24m

$1,055
Cheapest one-way
Quickest one-way

BostonSidney

BOS - SDY

BOSSDY

Boston Logan Intl

Mon 8/24

3:31 pm-9:07 am

2 stops19h 36m

$354

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/23

Sorted by cheapest first
  • Most accurate provider: When it comes to deals on Boston-Sidney, Montana flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Boston-Sidney, Montana flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Boston-Sidney, Montana flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Boston-Sidney, Montana flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Boston-Sidney, Montana flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Boston to Sidney

Have a flexible travel schedule? Discover the best time to fly to Sidney from Boston 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.

Related info for your journey

Find useful and relevant information for your journey from Boston to Sidney. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • Can I find deals for flights from Boston to Sidney that include hotel bookings?

    Yes. In addition to deals on Boston to Sidney flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Boston to Sidney?

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

  • Can I find deals for business class flights from Boston to Sidney?

    Yes. Cheapflights offers flight deals from Boston to Sidney by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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