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$456+ Cheap flights from Denver to Sidney, MT (DEN - SDY)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/11. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — SDY
Dec 12 — Dec 191
Fri 12/12
Fri 12/19
1 adult, Economy
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Cheap flight deals from Denver to Sidney

Discover tips and strategies to find the most affordable flight options for your journey from Denver (DEN) 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 November 12, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
1 star

Round-trip from

$456
(United)
Provider with most accurate pricing for Denver Intl-Sidney Richland Municipal flight deals.
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Provider most trusted by Cheapflights users for Denver Intl-Sidney Richland Municipal flights.
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From Denver Intl to Sidney Richland Municipal
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Find flight deals from Denver to Sidney

Cheapest flights from Denver to Sidney
Explore the most affordable flight options available from Denver to Sidney. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 12, 2025.

This United deal was found by Cheapflights users on 11/11. 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.
Thu 12/117:45 pmDEN - SDY
1 stop16h 44mMultiple Airlines
Thu 12/187:35 amSDY - DEN
1 stop24h 44mMultiple Airlines
Deal found 11/11$456

Cheapflights Fare Finder

 
Customize your flight search to find flights from Denver 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 November 12, 2025.
Use the filters below to find and compare flights from Denver to Sidney that are best for you.

Fly from

Denver

Fly to

Sidney

Route

Depart

Return

Price

DenverSidney

DEN - SDY

DENSDY

Denver Intl

Thu 12/11

7:45 pm-12:29 pm

1 stop16h 44m

Sidney Richland Municipal

Thu 12/18

7:35 am-8:19 am

1 stop24h 44m

$456

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/11

  • Most accurate provider: When it comes to deals on Denver-Sidney, Montana flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Denver-Sidney, Montana flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Denver-Sidney, Montana flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Denver-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 Denver-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 Denver to Sidney

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

What is the cheapest month to book a flight from Denver to Sidney, Montana?

Currently, April is the cheapest month in which you can book a flight from Denver to Sidney, Montana (average of $152). Flying from Denver to Sidney, Montana in July is currently the most expensive (average of $326). 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.

Related info for your journey

Find useful and relevant information for your journey from Denver 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 Denver to Sidney that include hotel bookings?

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

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

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

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

    Yes. Cheapflights offers flight deals from Denver 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.

  • What is the cheapest month to book a flight from Denver to Sidney, Montana?

    Currently, April is the cheapest month in which you can book a flight from Denver to Sidney, Montana (average of $152). Flying from Denver to Sidney, Montana in July is currently the most expensive (average of $326). 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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