$536+ 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 11/17. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — SDY
Nov 29 — Dec 61
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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
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
Cheapest
Best
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 October 30, 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 October 30, 2026.
This United deal was found by Cheapflights users on 10/29. 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.
Mon 11/98:00 am -
1 stop8h 32m
Fri 11/131:04 pm -
1 stop19h 34m
Deal found 10/29![Multiple Airlines logo]()
$536
This United deal was found by Cheapflights users on 10/29. 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.
Mon 11/911:50 am -
1 stop26h 26m
Thu 11/127:35 am -
1 stop25h 03m
Deal found 10/29![Multiple Airlines logo]()
$804
This Expedia deal was found by Cheapflights users on 10/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/177:03 am -
2 stops12h 41m
Thu 2/119:25 am -
2 stops13h 15m
Deal found 10/28![Multiple Airlines logo]()
$1,017
This KAYAK deal was found by Cheapflights users on 10/26. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/16:37 pm -
2 stops19h 39m
Sun 11/85:10 pm -
2 stops20h 48m
Deal found 10/26![Multiple Airlines logo]()
$1,297
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 October 30, 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 October 30, 2026.
This United deal was found by Cheapflights users on 10/28. 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.
Tue 11/178:00 am -
1 stop11h 44m
Thu 2/119:25 am -
1 stop6h 55m
Deal found 10/28![Multiple Airlines logo]()
$536
This United deal was found by Cheapflights users on 10/29. 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.
Mon 11/98:00 am -
1 stop8h 32m
Fri 11/131:04 pm -
1 stop19h 34m
Deal found 10/29![Multiple Airlines logo]()
$536
This United deal was found by Cheapflights users on 10/29. 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.
Mon 11/911:50 am -
1 stop26h 26m
Thu 11/127:35 am -
1 stop25h 03m
Deal found 10/29![Multiple Airlines logo]()
$804
Last-minute flights from Denver to SidneyDiscover last-minute flight deals from Denver to Sidney. Data last updated October 30, 2026 and is based on user searches.
Discover last-minute flight deals from Denver to Sidney. Data last updated October 30, 2026 and is based on user searches.
This KAYAK deal was found by Cheapflights users on 10/26. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/16:37 pm -
2 stops19h 39m
Sun 11/85:10 pm -
2 stops20h 48m
Deal found 10/26![Multiple Airlines logo]()
$1,297
This United deal was found by Cheapflights users on 10/29. 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.
Mon 11/98:00 am -
1 stop8h 32m
Fri 11/131:04 pm -
1 stop19h 34m
Deal found 10/29![Multiple Airlines logo]()
$536
This United deal was found by Cheapflights users on 10/29. 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.
Mon 11/911:50 am -
1 stop26h 26m
Thu 11/127:35 am -
1 stop25h 03m
Deal found 10/29![Multiple Airlines logo]()
$804
This Expedia deal was found by Cheapflights users on 10/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/177:03 am -
2 stops12h 41m
Thu 2/119:25 am -
2 stops13h 15m
Deal found 10/28![Multiple Airlines logo]()
$1,017
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 October 30, 2026.
Most accurate provider | Expedia 1 star |
|---|---|
Most trusted provider | Expedia 3 stars |
Round-trip from | $536 (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 October 30, 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
Tue 11/17
8:00 am-7:44 pm
1 stop11h 44m
Sidney Richland Municipal
Thu 2/11
9:25 am-4:20 pm
1 stop6h 55m
$536
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Mon 11/9
8:00 am-4:32 pm
1 stop8h 32m
Sidney Richland Municipal
Fri 11/13
1:04 pm-8:38 am
1 stop19h 34m
$536
DenverSidney
DEN Denver Intl - SDY Sidney Richland Municipal
DENSDY
Denver Intl
Mon 11/9
11:50 am-2:16 pm
1 stop26h 26m
Sidney Richland Municipal
Thu 11/12
7:35 am-8:38 am
1 stop25h 03m
$804
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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