$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 10/16. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — SDY
Oct 22 — Oct 291
Round-trip
1 adult, Economy
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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
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Denver to Sidney
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Last-minute
Cheapest flights from Denver to SidneyExplore 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 September 22, 2026.
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 September 22, 2026.
This United deal was found by Cheapflights users on 9/18. 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.
Fri 10/167:35 pm -
1 stop13h 23m
Fri 10/237:35 am -
1 stop12h 18m
Deal found 9/18![Multiple Airlines logo]()
$456
This Expedia deal was found by Cheapflights users on 9/20. 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 10/167:53 am -
2 stops11h 51m
Sun 10/187:35 am -
2 stops15h 02m
Deal found 9/20![Multiple Airlines logo]()
$1,041
This KAYAK deal was found by Cheapflights users on 9/22. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/245:41 pm -
2 stops15h 17m
Sat 9/267:35 am -
2 stops10h 35m
Deal found 9/22![Multiple Airlines logo]()
$1,530
Best flights from Denver to SidneyDiscover carefully curated flight deals from Denver to Sidney that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 22, 2026.
Discover carefully curated flight deals from Denver to Sidney that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 22, 2026.
This United deal was found by Cheapflights users on 9/18. 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.
Fri 10/167:35 pm -
1 stop13h 23m
Fri 10/237:35 am -
1 stop12h 18m
Deal found 9/18![Multiple Airlines logo]()
$456
This Expedia deal was found by Cheapflights users on 9/20. 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 10/167:53 am -
2 stops11h 51m
Sun 10/187:35 am -
2 stops15h 02m
Deal found 9/20![Multiple Airlines logo]()
$1,041
Last-minute flights from Denver to SidneyDiscover last-minute flight deals from Denver to Sidney. Data last updated September 22, 2026 and is based on user searches.
Discover last-minute flight deals from Denver to Sidney. Data last updated September 22, 2026 and is based on user searches.
This KAYAK deal was found by Cheapflights users on 9/22. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/245:41 pm -
2 stops15h 17m
Sat 9/267:35 am -
2 stops10h 35m
Deal found 9/22![Multiple Airlines logo]()
$1,530
This United deal was found by Cheapflights users on 9/18. 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.
Fri 10/167:35 pm -
1 stop13h 23m
Fri 10/237:35 am -
1 stop12h 18m
Deal found 9/18![Multiple Airlines logo]()
$456
This Expedia deal was found by Cheapflights users on 9/20. 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 10/167:53 am -
2 stops11h 51m
Sun 10/187:35 am -
2 stops15h 02m
Deal found 9/20![Multiple Airlines logo]()
$1,041
Find 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 September 22, 2026.
Most accurate provider | Expedia 1 star |
|---|---|
Most trusted provider | Expedia 3 stars |
Round-trip from | $456 (United) |
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 7,457,451 searches. Data last updated September 22, 2026.
Use the filters below to find and compare flights from Denver to Sidney that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Fri 10/16
7:35 pm-8:58 am
1 stop13h 23m
Sidney Richland Municipal
Fri 10/23
7:35 am-7:53 pm
1 stop12h 18m
$456
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Fri 10/16
7:53 am-7:44 pm
2 stops11h 51m
Sidney Richland Municipal
Sun 10/18
7:35 am-10:37 pm
2 stops15h 02m
$1,041
Sorted by cheapest first
- Most accurate provider: When it comes to deals on Denver-Sidney, Montana flights, users find the pricing of Expedia to be most consistent on Cheapflights vs. Expedia Users can find the same prices on Denver-Sidney, Montana flight deals on Cheapflights vs. Expedia <90% 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 Expedia the most. Expedia 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.
DEN-SDY
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
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