$441+ 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 10/27. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — SDY
Oct 29 — Nov 51
Round-trip
1 adult, Economy
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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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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 29, 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 29, 2026.
This United deal was found by Cheapflights users on 9/28. 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 10/169:10 pm -
1 stop22h 34m
Sun 10/185:10 pm -
1 stop26h 43m
Deal found 9/28![Multiple Airlines logo]()
$471
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 29, 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 29, 2026.
This United deal was found by Cheapflights users on 9/26. 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 1/18:15 am -
1 stop4h 11m
Thu 1/77:35 am -
1 stop8h 50m
Deal found 9/26![Multiple Airlines logo]()
$471
This United deal was found by Cheapflights users on 9/28. 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 10/169:10 pm -
1 stop22h 34m
Sun 10/185:10 pm -
1 stop26h 43m
Deal found 9/28![Multiple Airlines logo]()
$471
Last-minute flights from Denver to SidneyDiscover last-minute flight deals from Denver to Sidney. Data last updated September 29, 2026 and is based on user searches.
Discover last-minute flight deals from Denver to Sidney. Data last updated September 29, 2026 and is based on user searches.
This United deal was found by Cheapflights users on 9/28. 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 10/169:10 pm -
1 stop22h 34m
Sun 10/185:10 pm -
1 stop26h 43m
Deal found 9/28![Multiple Airlines logo]()
$471
One-way flights from Denver to SidneySearch for one-way flight options from Denver to Sidney. Find affordable one-way fares based on user searches. Data last updated September 29, 2026.
Search for one-way flight options from Denver to Sidney. Find affordable one-way fares based on user searches. Data last updated September 29, 2026.
This KAYAK deal was found by Cheapflights users on 9/28. 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.
Tue 10/2712:00 pm -
2 stops26h 16m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/28![Multiple Airlines logo]()
$441
This KAYAK deal was found by Cheapflights users on 9/28. 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 10/297:53 am -
2 stops11h 51m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/28![Multiple Airlines logo]()
$470
This KAYAK deal was found by Cheapflights users on 9/28. 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.
Mon 10/267:07 am -
2 stops31h 09m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/28![Multiple Airlines logo]()
$526
This KAYAK deal was found by Cheapflights users on 9/28. 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.
Sun 10/257:53 am -
2 stops11h 51m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/28![Multiple Airlines logo]()
$610
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 29, 2026.
Most accurate provider | Expedia 1 star |
|---|---|
Most trusted provider | Expedia 3 stars |
Round-trip from | $471 (United) |
One-way from | $441 (KAYAK) |
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 29, 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
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Tue 10/27
12:00 pm-2:16 pm
2 stops26h 16m
Sidney Richland Municipal
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$441
Quickest round-trip
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Thu 10/29
7:53 am-7:44 pm
2 stops11h 51m
Sidney Richland Municipal
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$470
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Fri 1/1
8:15 am-12:26 pm
1 stop4h 11m
Sidney Richland Municipal
Thu 1/7
7:35 am-4:25 pm
1 stop8h 50m
$471
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Fri 10/16
9:10 pm-7:44 pm
1 stop22h 34m
Sidney Richland Municipal
Sun 10/18
5:10 pm-7:53 pm
1 stop26h 43m
$471
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Mon 10/26
7:07 am-2:16 pm
2 stops31h 09m
Sidney Richland Municipal
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$526
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Sun 10/25
7:53 am-7:44 pm
2 stops11h 51m
Sidney Richland Municipal
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$610
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
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.
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