Cheap Flights from Seattle (SEA) to Sion (SIR)

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Frequently asked questions

How much does a flight from Seattle - Tacoma Intl. Airport (SEA) to Sion Airport (SIR) cost?
Discover the latest flight deals from SEA to SIR by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from SEA to SIR?
The cheapest flights from SEA to SIR are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from SEA to SIR?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from SEA to SIR. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Seattle - Tacoma Intl. Airport (SEA) to Sion Airport (SIR)?
You’ll need to take a flight with a layover if you’re traveling from Seattle - Tacoma Intl. Airport (SEA) to Sion Airport (SIR). Direct flights don’t operate daily on this route. However, just filter your search to include one or two stops to discover the best option for your trip.
What day of the week has the most flights from SEA to SIR?
Friday is generally the busiest day for flights, while Tuesday tends to be the quietest.* Remember that flight schedules can change depending on a number of factors, including the season 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 Seattle - Tacoma Intl. Airport (SEA) to Sion Airport (SIR)?
To touch down at Sion Airport (SIR) on time, opt for a flight that takes off from Seattle - Tacoma Intl. Airport (SEA) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this hour.**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 Seattle - Tacoma Intl. Airport (SEA) to Sion Airport (SIR) last-minute?
Last-minute fares from SEA to SIR are typically more expensive. For the lowest rates, start searching for flights well in advance. That being said, if your travel plans are flexible, it’s possible to find a cheap fare right before your journey.
Is it cheaper to book a SEA to SIR flight and hotel package?
Compared with arranging flights and hotels separately, booking a SEA to SIR flight and hotel package with Expedia could lead to significant savings. What’s more, managing everything in one place takes the hassle out of travel planning. Just secure your flights and choose from our extensive range of hotels, then personalize your trip with extras like tours, activities and car rentals.
Can I cancel or change the date of my flight from Seattle - Tacoma Intl. Airport (SEA) to Sion Airport (SIR)?
If you reserved your SEA to SIR flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the ticket type you purchased, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, go to our Customer Service portal for more details.
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