The cheapest times to fly from IAD to SDY are

  • January 1st to March 4th
  • August 6th to December 9th (except the week of November 19th)

based on data collected exclusively by Champion Traveler across tens of millions of flights. Among all the dates above, the very cheapest time to fly from IAD to SDY is mid to late September. Prices can be as high as $983 for Sunday flights during early to mid June, or as low as $494 for Wednesday flights around mid to late September.


When to Fly to Sidney

Flying from Washington, DC (IAD) to Sidney, MT (SDY) will usually cost between $586 to $884 per person if booking more than four weeks in advance. On average the very cheapest time to fly is mid to late September with an average ticket price of $554. Due to high demand the most expensive time to fly is early to mid June, with an average price of $855. Planning your trip to low-cost times can easily save you $301 on economy flights and even more on first-class flights. Generally, any price below $736 can be considered a good price for a round-trip IAD to SDY flight.

See below for a graph of average weekly prices for the IAD to SDY route. All prices are for round-trip tickets in USD.

IAD to SDY Flight Prices

Compared to other flights, the IAD to SDY flight is cheaper than the average and costs less than the average flight leaving from Washington. The average price per mile (for a direct flight) is $0.31, which is in the normal range for a flight.


Flight Prices by Day of the Week

Wednesday is usually the cheapest day to fly to SDY, and Tuesday the cheapest day to fly back into IAD. Sundays are the most expensive days to fly out or take a return trip. Selecting flights on the least expensive days could save you up to $79 (10%) on this flight.

Departing prices are for round-trip flights returning on the day of departure. For example, a flight departing on Wednesday and returning a week later will cost an average of $707. Return trip prices are from the SDY to IAD flight, and often highlight the quality of our data in showing the same trend.

Departing Prices by Day

Departure Day Prices

Return Trip Prices by Day

Return Day Prices


Nonstop Flights and Layovers

Travelers looking to fly from IAD to SDY can generally find a 2-layover flight. Because there is not usually a direct flight option the real-world direct flight time of 3 hour 37 minutes may not be realistic.


Alternative Nearby Airports

Champion Traveler tells you which airports are nearby and whether tickets might be cheaper alternative airports nearby. Sometimes it’s worth it to fly into a closer airport and then commute to your destination. Remember that there is not usually a nonstop flight from IAD to SDY while comparing.

Destination alternative #1: Minot International Airport (MOT) in Minot, ND

  • 140 miles (225 km) away from SDY
  • Usually 37.66% less expensive than SDY
  • 1-layover flights available

See IAD to MOT flights

Destination alternative #2: Dickinson – Theodore Roosevelt Regional Airport (DIK) in Dickinson, ND

  • 91 miles (146 km) away from SDY
  • Usually 6.19% less expensive than SDY
  • 1-layover flights available

See IAD to DIK flights


Flight Hacking IAD to SDY

Flight hacking is when you book two tickets instead of a layover, sometimes with different airlines. You will need to either bring only a carry-on bag (highly recommended) or leave yourself plenty of time to go through security again. Flight hacking is completely allowed, but airlines don’t always tell you the cheapest way to get from IAD to SDY — but Champion Traveler does!

Hack #1: Billings, MT (IAD > BIL > SDY)

  • Price for both tickets: $514
  • Average savings: $222 (30.12%)

See IAD to BIL flights


Flight Questions Answered

Still have questions about flying from IAD to SDY? We’ve got answers.

Which airlines fly this route?

You can find 6 major airlines flying this route most often: Alaska, American, Cape Air, Delta, Frontier, United, and potentially more during busy seasons.

How far away is it from Sidney Richland Regional Airport to Washington Dulles International Airport?

The distance between the two airports is roughly 1464 miles or 2356 kilometers.

How long does it take to fly from IAD to SDY?

The real-world flight time for a nonstop IAD to SDY flight is about 3 hour 37 minutes.

How many flights go between Washington, DC and Sidney, MT?

It depends on the day of the week and the date, but a typical day might have around 17 available flights from IAD to SDY.


Airport Location Info


Departing Airport

Origination codeIAD
Origination airport nameWashington Dulles International Airport
CityWashington, DC
Countrythe United States

Return Airport

Destination codeSDY
Destination airport nameSidney Richland Regional Airport
CitySidney, MT
Countrythe United States


Other Resources

Please note that while we’ve worked hard to analyzed tens of millions of flights to get you this data, we do not calculate current live prices or guarantee pricing. Please see our partners using the links above for current offers.