$777 Cheap Flights from St. Louis (STL) to Perth (PER)

View $777 flight on Sun, Sep 7, 2025Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Perth Airport (PER)

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Cheap Flights from St. Louis to Perth (STL-PER)

Prices were available within the past 7 days and start at $777 for one-way flights and $1,458 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Air Canada
Mon, Mar 9 - Tue, Mar 17
STL
St. Louis
PER
Perth
$1,458 Roundtrip, found 3 days ago
$1,458
Roundtrip
found 3 days ago
Select Air Canada flight, departing Mon, Mar 9 from St. Louis to Perth, returning Tue, Mar 17, priced at $1,458 found 3 days ago
Air Canada
Tue, Sep 23 - Tue, Sep 30
STL
St. Louis
PER
Perth
$1,478 Roundtrip, found 6 days ago
$1,478
Roundtrip
found 6 days ago
Select Air Canada flight, departing Tue, Sep 23 from St. Louis to Perth, returning Tue, Sep 30, priced at $1,478 found 6 days ago
Air Canada
Tue, Sep 23 - Tue, Sep 30
STL
St. Louis
PER
Perth
$1,493 Roundtrip, found 6 days ago
$1,493
Roundtrip
found 6 days ago
Select Air Canada flight, departing Tue, Sep 23 from St. Louis to Perth, returning Tue, Sep 30, priced at $1,493 found 6 days ago
Air Canada
Tue, Sep 23 - Tue, Sep 30
STL
St. Louis
PER
Perth
$1,502 Roundtrip, found 6 days ago
$1,502
Roundtrip
found 6 days ago
Select Air Canada flight, departing Tue, Sep 23 from St. Louis to Perth, returning Tue, Sep 30, priced at $1,502 found 6 days ago
Air Canada
Tue, Sep 23 - Tue, Sep 30
STL
St. Louis
PER
Perth
$1,517 Roundtrip, found 6 days ago
$1,517
Roundtrip
found 6 days ago
Select Air Canada flight, departing Tue, Sep 23 from St. Louis to Perth, returning Tue, Sep 30, priced at $1,517 found 6 days ago
American Airlines
Wed, Sep 10 - Mon, Sep 15
STL
St. Louis
PER
Perth
$1,542 Roundtrip, found 21 hours ago
$1,542
Roundtrip
found 21 hours ago
Select American Airlines flight, departing Wed, Sep 10 from St. Louis to Perth, returning Mon, Sep 15, priced at $1,542 found 21 hours ago
Qantas Airways
Wed, Sep 10 - Wed, Sep 17
STL
St. Louis
PER
Perth
$1,552 Roundtrip, found 5 days ago
$1,552
Roundtrip
found 5 days ago
Select Qantas Airways flight, departing Wed, Sep 10 from St. Louis to Perth, returning Wed, Sep 17, priced at $1,552 found 5 days ago
Qantas Airways
Wed, Sep 10 - Wed, Sep 17
STL
St. Louis
PER
Perth
$1,555 Roundtrip, found 5 days ago
$1,555
Roundtrip
found 5 days ago
Select Qantas Airways flight, departing Wed, Sep 10 from St. Louis to Perth, returning Wed, Sep 17, priced at $1,555 found 5 days ago
Cathay Pacific
Tue, Sep 9 - Mon, Sep 15
STL
St. Louis
PER
Perth
$1,561 Roundtrip, found 21 hours ago
$1,561
Roundtrip
found 21 hours ago
Select Cathay Pacific flight, departing Tue, Sep 9 from St. Louis to Perth, returning Mon, Sep 15, priced at $1,561 found 21 hours ago
Qatar Airways
Tue, Sep 9 - Tue, Sep 16
STL
St. Louis
PER
Perth
$1,568 Roundtrip, found 8 hours ago
$1,568
Roundtrip
found 8 hours ago
Select Qatar Airways flight, departing Tue, Sep 9 from St. Louis to Perth, returning Tue, Sep 16, priced at $1,568 found 8 hours ago

Alternative airports near Perth

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Perth Airport PER. Cheapest and Closest option available. Average driving time to city center is 14 minutes. Flights from $1,622
PER
Perth Airport
CheapestClosest
Average driving time to city center14 min
Flights from $1,622
Flights from St. Louis (STL) to Perth (PER)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Perth
Airlines serving
Air Canada, American Airlines, Cathay Pacific, Qantas Airways, Qatar Airways, United
Roundtrip price
$1,458
Distance
10885 mi

St. Louis to Perth Flights

The cheapest times to fly from St. Louis to Perth

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 St. Louis to Perth are during the month of March. You can find some of the cheapest flights from St. Louis to Perth with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Perth

Sunday is one of the best days to book for cheap flights from St. Louis to Perth: 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 St. Louis to Perth

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 St. Louis to Perth in 2025. You can also book with separate airlines for your outbound and return journeys, from $777 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 St. Louis to Perth 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 St. Louis to Perth 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 Lambert-St. Louis Intl. Airport (STL) to Perth Airport (PER) cost?
Discover the latest flight deals from STL to PER 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 STL to PER?
The cheapest flights from STL to PER 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 STL to PER?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that'll take you from STL to PER. Sort your results by "Price (lowest to highest)" to snap up a great deal.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Perth Airport (PER)?
You'll need to book a flight with a layover when traveling from Lambert-St. Louis Intl. Airport (STL) to Perth Airport (PER). There are no daily direct flights on this route. However, just filter your search to include one or two stops to find the best option for your trip.
What day of the week has the most flights from STL to PER?
Friday is usually the busiest day for flights, while Tuesday is often the quietest.* Remember that flight schedules can vary based on a range of factors, including the time of year and carrier.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Perth Airport (PER)?
To arrive at Perth Airport (PER) on schedule, choose a flight that leaves Lambert-St. Louis Intl. Airport (STL) before 3 PM. The chance of cancellations is 22% higher, on average, for departures after this time.**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 Lambert-St. Louis Intl. Airport (STL) to Perth Airport (PER) last-minute?
Last-minute bookings from STL to PER are typically more expensive. For the best rates, start searching for flights well ahead of time. That said, if you can play around with your travel dates, it's possible to find a cheap fare right before your journey.
Is it cheaper to book a STL to PER flight and hotel package?
Compared with arranging flights and hotels separately, booking a STL to PER flight and hotel package with Expedia could lead to significant savings. Better still, having it all in one place will take the stress out of planning your trip. Just secure your flights and choose from our extensive range of stays, then personalize your trip with other add-ons like tours, activities and car rentals.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Perth Airport (PER)?
In most cases, you can reschedule or cancel your STL to PER flight. However, additional charges may apply, especially if you booked more than 24 hours ago. Check your itinerary for the airline's fees and guidelines on flight changes, or if you want further details, head to our Customer Service portal.

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*Available to One Key members.