$401 Cheap Flights from Redmond (RDM) to Sidney (SDY)

View $401 flight on Tue, Mar 24, 2026Opens in a new window

Popular airlines from Redmond Municipal Airport (RDM) to Sidney, MT (SDY-Sidney-Richland Municipal)

Cheap Flights from Redmond to Sidney (RDM-SDY)

Prices were available within the past 7 days and start at $401 for one-way flights and $1,055 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,055 Roundtrip, found 4 days ago
$1,055
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,055 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,065 Roundtrip, found 4 days ago
$1,065
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,065 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,076 Roundtrip, found 4 days ago
$1,076
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,076 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,086 Roundtrip, found 4 days ago
$1,086
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,086 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,115 Roundtrip, found 4 days ago
$1,115
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,115 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,116 Roundtrip, found 4 days ago
$1,116
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,116 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,125 Roundtrip, found 4 days ago
$1,125
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,125 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,126 Roundtrip, found 4 days ago
$1,126
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,126 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,135 Roundtrip, found 4 days ago
$1,135
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,135 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,145 Roundtrip, found 4 days ago
$1,145
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,145 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,175 Roundtrip, found 4 days ago
$1,175
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,175 found 4 days ago
Alaska Airlines
Tue, Mar 24 - Sat, Mar 28
RDM
Redmond
SDY
Sidney
$1,185 Roundtrip, found 4 days ago
$1,185
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Tue, Mar 24 from Redmond to Sidney, returning Sat, Mar 28, priced at $1,185 found 4 days ago

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Frequently asked questions

How much does a flight from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) cost?
You can find cheap one-way flights from $401 and cheap return flights from $1,055 RDM to SDY with Expedia. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see our cheapest fares first, and use the Price Tracking tool to receive alerts when RDM to SDY ticket fares go up or down.
What is the cheapest month to fly from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
The cheapest month to fly from RDM to SDY is March when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you're able to. Use the calendar view in your search to see which months have low fares on this route.
Which airlines fly direct from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
Enter RDM to SDY and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
What is the cheapest airline that flies from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
Alaska Airlines, Delta and United are just some of the carriers that fly from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal). Use Expedia's flight search tool to compare airlines on this route and find our cheapest option for your trip. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.*Prices based on flights available on Expedia in the last year.
How do I find cheap flights from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
To find a cheap flight from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
What is the earliest flight from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
Sort flights by "Departure (earliest)" on Expedia to find the earliest flight from RDM to SDY. To compare more early flights, use the "Early Morning" and "Morning" filters in your search.
How long does it take to fly from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
Flights from RDM to SDY with one stop typically take around 10 hours 50 minutes, covering approximately 847 miles. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
Select the "Business class" and "First class" filters when looking for RDM to SDY flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How do I earn miles on a Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) flight with Expedia?
It's easy to earn miles on a Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
Is it cheaper to buy a plane ticket from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) at the last minute?
Typically, booking a last minute flight from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) flight and hotel package?
Securing a Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal)?
If you booked your Redmond, OR (RDM-Robert's Field) to Sidney, MT (SDY-Sidney-Richland Municipal) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Robert's Field
Destination airport
Sidney-Richland Municipal
Roundtrip price
$1,054
Distance
847 mi

Book with confidence

Redmond to Sidney Flights

The cheapest times to fly from Redmond 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 Redmond to Sidney are during the month of March. You can find some of the cheapest flights from Redmond to Sidney with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Redmond to Sidney

Sunday is one of the best days to book for cheap flights from Redmond 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 Redmond 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 Redmond to Sidney in 2026. You can also book with separate airlines for your outbound and return journeys, from $401 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 Redmond 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 Redmond 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.

 

Redmond to Sidney Flights

*Flight schedules are subject to change.

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*Available to One Key members.