HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Sidney

$660+ 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 5/1. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — SDY
May 2 — May 91
Sat 5/2
Sat 5/9
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Denver to Sidney with Cheapflights

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 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 April 2, 2026.

This KAYAK deal was found by Cheapflights users on 3/30. 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.
Fri 5/16:07 pm
DEN
-
SDY
2 stops39h 03m
Multiple Airlines
Sun 5/35:10 pm
SDY
-
DEN
2 stops25h 19m
Multiple Airlines
Deal found 3/30$660
This Travelocity deal was found by Cheapflights users on 4/1. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/296:00 am
DEN
-
SDY
2 stops13h 51m
Multiple Airlines
Wed 5/67:35 am
SDY
-
DEN
2 stops14h 14m
Multiple Airlines
Deal found 4/1$720
This Expedia deal was found by Cheapflights users on 3/31. 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.
Mon 4/134:21 pm
DEN
-
SDY
2 stops16h 49m
Multiple Airlines
Thu 4/169:45 am
SDY
-
DEN
2 stops8h 43m
Multiple Airlines
Deal found 3/31$965
This Expedia deal was found by Cheapflights users on 3/29. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/134:21 pm
DEN
-
SDY
2 stops16h 49m
Multiple Airlines
Fri 4/177:35 am
SDY
-
DEN
2 stops10h 53m
Multiple Airlines
Deal found 3/29$1,025

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 April 2, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$660
(KAYAK)
Provider with most accurate pricing for Denver Intl-Sidney Richland Municipal flight deals.
Search Deals
Provider most trusted by Cheapflights users for Denver Intl-Sidney Richland Municipal flights.
Search Deals
From Denver Intl to Sidney Richland Municipal
Search Deals

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 April 2, 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

Price

Cheapest round-trip

DenverSidney

DEN - SDY

DENSDY

Denver Intl

Fri 5/1

6:07 pm-9:10 am

2 stops39h 03m

Sidney Richland Municipal

Sun 5/3

5:10 pm-6:29 pm

2 stops25h 19m

$660

DenverSidney

DEN - SDY

DENSDY

Denver Intl

Wed 4/29

6:00 am-7:51 pm

2 stops13h 51m

Sidney Richland Municipal

Wed 5/6

7:35 am-9:49 pm

2 stops14h 14m

$720
Quickest round-trip

DenverSidney

DEN - SDY

DENSDY

Denver Intl

Mon 4/13

4:21 pm-9:10 am

2 stops16h 49m

Sidney Richland Municipal

Thu 4/16

9:45 am-6:28 pm

2 stops8h 43m

$965

DenverSidney

DEN - SDY

DENSDY

Denver Intl

Mon 4/13

4:21 pm-9:10 am

2 stops16h 49m

Sidney Richland Municipal

Fri 4/17

7:35 am-6:28 pm

2 stops10h 53m

$1,025

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/30

Sorted by cheapest first
  • 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, January is the cheapest month in which you can book a flight from Denver to Sidney, Montana (average of $199). 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, January is the cheapest month in which you can book a flight from Denver to Sidney, Montana (average of $199). 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.