$751 Cheap Flights from Idaho Falls (IDA) to Sidney (SDY)

View $751 flight on Sat, Nov 1, 2025Opens in a new window

Popular airlines from Idaho Falls Regional Airport (IDA) to Sidney, MT (SDY-Sidney-Richland Municipal)

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Cheap Flights from Idaho Falls to Sidney (IDA-SDY)

Prices were available within the past 7 days and start at $751 for one-way flights and for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Flights from Idaho Falls (IDA) to Sidney (SDY)
Origin airport
Idaho Falls Regional
Destination airport
Sidney-Richland Municipal
Distance
478 mi

Idaho Falls to Sidney Flights

The cheapest times to fly from Idaho Falls to Sidney

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Idaho Falls to Sidney are during the month of . You can find some of the cheapest flights from Idaho Falls to Sidney with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Idaho Falls to Sidney

Sunday is one of the best days to book for cheap flights from Idaho Falls to Sidney: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Idaho Falls to Sidney

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Idaho Falls to Sidney in 2025. You can also book with separate airlines for your outbound and return journeys, from $751 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Idaho Falls to Sidney flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Idaho Falls to Sidney airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY) cost?
Secure a cheap one-way flight from $751 or cheap return flight from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight offers on this route.
What is the cheapest month to fly from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY)?
Flying in can help you save, as it's the cheapest month for flights between IDA and SDY. You'll often find the lowest fares during the off-season.
What is the cheapest airline that flies from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY)?
Expedia's filter tool lets you easily compare travel time, airlines and fares all in one place. Customize the search to your preferences, then sort by "Price (lowest to highest)" to see which carrier offers the cheapest IDA to SDY flight.
How many flights per day from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY)?
There are no daily direct flights available from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY). But you can choose flights with layovers. Filter your search on Expedia to include one or more stops, and you'll be cruising above the clouds before you know it.
What day of the week has the most flights from IDA to SDY?
Friday is generally the busiest day for flights, while Tuesday tends to be the quietest.* Remember that flight schedules can change based on various factors, including the time of year and airline.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY)?
Choose a flight from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY) that takes off before 3 PM to reduce the risk of delays and cancellations. Departures after this hour have a 22% higher chance of being canceled, on average.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY) last-minute?
Holding off until just before your departure to book your flight from IDA to SDY often results in higher prices. While it's possible to find some last-minute offers, there's no guarantee. Keep your travel schedule open for the best chance of landing a bargain.
Is it cheaper to book an IDA to SDY flight and hotel package?
Securing an IDA to SDY flight and hotel package tends to be cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your trip in one place. Pick from our wide range of accommodations and then add flights, car rentals and activities to your booking. Bundle it all together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Idaho Falls Regional Airport (IDA) to Sidney-Richland Municipal Airport (SDY)?
If you reserved your IDA to SDY flight within the last 24 hours, you may be able to modify or cancel it at no cost. Depending on the airline and the type of ticket you have, additional charges may apply for changes after that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal for further details.

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