$562 Cheap Flights from St. Louis (STL) to Sydney (SYD)

View $562 flight on Mon, Mar 9, 2026Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Sydney Airport (SYD)

Cheap Flights from St. Louis to Sydney (STL-SYD)

Prices were available within the past 7 days and start at $562 for one-way flights and $1,141 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Air Canada
Tue, May 5 - Tue, May 26
STL
St. Louis
SYD
Sydney
$1,141 Roundtrip, found 1 day ago
$1,141
Roundtrip
found 1 day ago
Select Air Canada flight, departing Tue, May 5 from St. Louis to Sydney, returning Tue, May 26, priced at $1,141 found 1 day ago
Air Canada
Tue, May 5 - Tue, May 26
STL
St. Louis
SYD
Sydney
$1,143 Roundtrip, found 1 day ago
$1,143
Roundtrip
found 1 day ago
Select Air Canada flight, departing Tue, May 5 from St. Louis to Sydney, returning Tue, May 26, priced at $1,143 found 1 day ago
Air Canada
Tue, Sep 8 - Tue, Sep 15
STL
St. Louis
SYD
Sydney
$1,152 Roundtrip, found 1 day ago
$1,152
Roundtrip
found 1 day ago
Select Air Canada flight, departing Tue, Sep 8 from St. Louis to Sydney, returning Tue, Sep 15, priced at $1,152 found 1 day ago
Air Canada
Tue, Feb 10 - Mon, Feb 16
STL
St. Louis
SYD
Sydney
$1,154 Roundtrip, found 18 hours ago
$1,154
Roundtrip
found 18 hours ago
Select Air Canada flight, departing Tue, Feb 10 from St. Louis to Sydney, returning Mon, Feb 16, priced at $1,154 found 18 hours ago
Hawaiian Airlines
Wed, Feb 4 - Fri, Feb 13
STL
St. Louis
SYD
Sydney
$1,187 Roundtrip, found 2 days ago
$1,187
Roundtrip
found 2 days ago
Select Hawaiian Airlines flight, departing Wed, Feb 4 from St. Louis to Sydney, returning Fri, Feb 13, priced at $1,187 found 2 days ago
Air Canada
Thu, Feb 19 - Wed, Feb 25
STL
St. Louis
SYD
Sydney
$1,187 Roundtrip, found 18 hours ago
$1,187
Roundtrip
found 18 hours ago
Select Air Canada flight, departing Thu, Feb 19 from St. Louis to Sydney, returning Wed, Feb 25, priced at $1,187 found 18 hours ago
American Airlines
Mon, Jan 19 - Mon, Feb 9
STL
St. Louis
SYD
Sydney
$1,278 Roundtrip, just found
$1,278
Roundtrip
just found
Select American Airlines flight, departing Mon, Jan 19 from St. Louis to Sydney, returning Mon, Feb 9, priced at $1,278 just found
United
Mon, Jan 19 - Mon, Feb 9
STL
St. Louis
SYD
Sydney
$1,291 Roundtrip, just found
$1,291
Roundtrip
just found
Select United flight, departing Mon, Jan 19 from St. Louis to Sydney, returning Mon, Feb 9, priced at $1,291 just found
Delta
Wed, Jan 21 - Wed, Feb 4
STL
St. Louis
SYD
Sydney
$1,295 Roundtrip, found 4 days ago
$1,295
Roundtrip
found 4 days ago
Select Delta flight, departing Wed, Jan 21 from St. Louis to Sydney, returning Wed, Feb 4, priced at $1,295 found 4 days ago
All Nippon Airways
Tue, Aug 18 - Tue, Sep 8
STL
St. Louis
SYD
Sydney
$1,310 Roundtrip, found 6 days ago
$1,310
Roundtrip
found 6 days ago
Select All Nippon Airways flight, departing Tue, Aug 18 from St. Louis to Sydney, returning Tue, Sep 8, priced at $1,310 found 6 days ago

Find the cheapest month to fly from St. Louis (STL) to Sydney (SYD)

September is typically the cheapest month to fly

From $1,081 - $1,746 per traveler.

Alternative airports near Sydney

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

Select flight to Kingsford Smith Intl. SYD. Cheapest option available. Average driving time to city center is 16 minutes. Flights from $1,591
SYD
Kingsford Smith Intl.
Cheapest
Average driving time to city center16 min
Flights from $1,591

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD) cost?
Secure a cheap one-way flight from $562 or cheap return flight from $1,141 from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight deals on this route.
What is the cheapest month to fly from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD)?
Planning your trip for May is a good way to save, as it's the cheapest month for flights between STL and SYD. You'll usually find the lowest prices during the off-season.
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD)?
Expedia's filter tool lets you easily compare different airlines, travel time and fares all in one place. Select your preferences, then sort by "Price (lowest to highest)" to find out which carrier offers the cheapest STL to SYD flight.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD)?
Direct flights from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD) aren't available daily, so you'll need to take a flight with a layover. Explore your options with our filter tool. Enter your dates and click on either "1 Stop" or "2+ Stops."
What day of the week has the most flights from STL to SYD?
Generally you'll find the greatest selection of flight options on a Friday. Tuesdays tend to be the quietest.* But this can vary based on the time of year, carrier and other factors.*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 Kingsford Smith Intl. Airport (SYD)?
Select a flight from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD) that leaves before 3 PM to reduce the likelihood of delays. Departures later than this 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 Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD) last-minute?
Booking your plane ticket from STL to SYD shortly before your trip is generally more expensive. But if there's some wiggle room with your departure dates and times, you could snag a cheap last-minute fare.
Is it cheaper to book a STL to SYD flight and hotel package?
You'll generally save money by booking a STL to SYD flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it's simple to manage it all in one convenient place. After choosing your preferred accommodations and flights, consider adding extras including car rentals, activities and tours.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Kingsford Smith Intl. Airport (SYD)?
In most cases, you can reschedule or cancel your STL to SYD flight. However, there may be additional charges, especially if your booking was made more than 24 hours ago. Double-check your itinerary for the airline's guidelines and fees on flight changes, or if you'd like further information, head to our Customer Service portal.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Kingsford Smith Intl.
Airlines serving
Air Canada, Air New Zealand, Alaska Airlines, All Nippon Airways, American Airlines, Asiana Airlines, British Airways, Cathay Pacific, Delta, Hawaiian Airlines, Japan Airlines, Lufthansa, Qantas Airways, Qatar Airways, Turkish Airlines, United
Roundtrip price
$1,141
Distance
9060 mi

Book with confidence

St. Louis to Sydney Flights

The cheapest times to fly from St. Louis to Sydney

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

 

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

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

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 Sydney in 2025. You can also book with separate airlines for your outbound and return journeys, from $562 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 Sydney 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 Sydney 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.

 

St. Louis to Sydney Flights

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*Available to One Key members.