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$616+ Cheap flights from St. Louis (STL) to Sydney (SYD)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/31. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SYD
Aug 26 — Sep 21
Wed 8/26
Wed 9/2
1 adult, Economy
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Cheap flight deals from St. Louis to Sydney

Cheapest flights from St. Louis to Sydney
Explore the most affordable flight options available from St. Louis to Sydney. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 27, 2026.

This oojo deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/132:54 pm
STL
-
SYD
2 stops33h 46m
Qantas Airways
Thu 11/2611:20 am
SYD
-
STL
1 stop29h 25m
Qantas Airways
Deal found 7/26$1,079
This oojo deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/96:02 am
STL
-
SYD
1 stop33h 58m
Qantas Airways
Thu 11/195:50 pm
SYD
-
STL
2 stops41h 25m
Qantas Airways
Deal found 7/23$1,089
This Air Canada deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/812:10 pm
STL
-
SYD
2 stops28h 10m
Air Canada
Wed 9/309:20 am
SYD
-
STL
2 stops48h 21m
Air Canada
Deal found 7/25$1,111
This Air Canada deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/1112:10 pm
STL
-
SYD
2 stops28h 10m
Air Canada
Mon 10/1910:20 am
SYD
-
STL
2 stops48h 21m
Air Canada
Deal found 7/23$1,112
This Air Canada deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/238:55 am
STL
-
SYD
2 stops31h 25m
Air Canada
Wed 10/710:20 am
SYD
-
STL
2 stops24h 21m
Air Canada
Deal found 7/27$1,116
This Air Canada deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/712:10 pm
STL
-
SYD
3 stops52h 10m
Air Canada
Sun 9/279:20 am
SYD
-
STL
2 stops48h 21m
Air Canada
Deal found 7/25$1,119
This Justfly.com deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/135:10 am
STL
-
SYD
2 stops35h 10m
Air Canada
Tue 9/229:20 am
SYD
-
STL
3 stops41h 37m
Air Canada
Deal found 7/23$1,121
This FlightHub deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/1312:10 pm
STL
-
SYD
2 stops28h 10m
Air Canada
Wed 11/1811:20 am
SYD
-
STL
1 stop45h 06m
Air Canada
Deal found 7/26$1,126

Find flight deals from St. Louis to Sydney

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Sydney (SYD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated July 27, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,111
(Air Canada)

One-way from

$616
(oojo)

Popular in

December

Cheapest in

July

Average price

$1,161
Provider with most accurate pricing for Lambert-St Louis-Sydney Kingsford Smith flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Sydney Kingsford Smith flights.
Search Deals
From Lambert-St Louis to Sydney Kingsford Smith
Search Deals
One-way flight from Lambert-St Louis to Sydney Kingsford Smith
Search Deals
Highest demand for flights based on searches. 6% potential increase in price ($97 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($19 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Sydney that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 27, 2026.
Use the filters below to find and compare flights from St. Louis to Sydney that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 9/7

12:10 pm-7:20 am

3 stops52h 10m

Sydney Kingsford Smith

Sun 9/27

9:20 am-6:41 pm

2 stops48h 21m

$1,119

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 8/5

6:01 am-6:55 am

2 stops33h 54m

Sydney Kingsford Smith

Wed 8/12

10:20 am-6:39 pm

1 stop23h 19m

$1,170
Quickest round-trip

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 9/14

4:40 pm-6:55 am

2 stops23h 15m

Sydney Kingsford Smith

Sun 9/27

9:30 am-6:43 pm

2 stops24h 13m

$1,170

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 9/23

12:46 pm-7:05 am

2 stops27h 19m

Sydney Kingsford Smith

Wed 10/7

1:00 pm-11:42 pm

1 stop26h 42m

$1,171

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 10/21

3:20 pm-6:55 am

1 stop23h 35m

Sydney Kingsford Smith

Sun 10/25

7:40 pm-11:46 pm

2 stops44h 06m

$1,224

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Fri 10/9

6:04 am-8:05 am

1 stop34h 01m

Sydney Kingsford Smith

Sun 10/18

6:05 pm-6:20 pm

2 stops40h 15m

$1,463

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 8/5

1:38 pm-10:40 am

3 stops30h 02m

Sydney Kingsford Smith

Wed 8/12

9:55 am-11:40 pm

3 stops28h 45m

$2,146

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 7/30

1:13 pm-8:45 am

3 stops28h 32m

Sydney Kingsford Smith

Sat 8/1

11:55 am-11:47 pm

3 stops26h 52m

$2,445
Cheapest one-way

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 8/31

8:00 am-7:05 am

2 stops32h 05m

$616

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 8/12

8:00 am-7:05 am

2 stops32h 05m

$622

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/22

Showing 1-10 of 13 resultsSorted by cheapest first
1
2

Compare providers for flights from St. Louis to Sydney

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Sydney in July.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy2 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-Sydney flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Sydney flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Sydney flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Sydney flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Sydney flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from St. Louis to Sydney

Have a flexible travel schedule? Discover the best time to fly to Sydney from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Sydney

What is the cheapest month to book a flight from St. Louis to Sydney?

Currently, July is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,161). Flying from St. Louis to Sydney in December is currently the most expensive (average of $1,634). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

How much does it cost to fly round-trip from St. Louis to Sydney?

Airfare is below average for this route at the moment.

St. Louis to Sydney flights typically cost between $1,314 and $1,554 in November.
The cheapest round-trip price found within the last 5 days was $1,079 on Qantas Airways (Nov 13-Nov 26).

Reviews of airlines servicing Sydney

Get insights into the airlines that provide service to Sydney. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Sydney. Reviews last updated July 27, 2026.
Get a feel of what it's like to fly with Qantas Airways,United Airlines, andAmerican Airlines from St. Louis to Sydney by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Qantas Airways
7.5
Good
1,067 reviews

Crew

8.1

Entertainment

7.2

Food

7.0

Comfort

7.4

Boarding

7.7

Overall

7.5

Reviews

1 / 20
2.0
Mediocre

Anonymous,Jul 2025

MEL - SYD

Flight cancelled 2hours before take off after checking in. Booked by airline on flight 6 hours later. No compensation or vouchers till we asked just before the flight took off.
Qantas Airways
7.5
Good
1,067 reviews
Qantas Airways
7.5
Good
1,067 reviews

Crew

8.1

Entertainment

7.2

Food

7.0

Comfort

7.4

Boarding

7.7

Overall

7.5

Reviews

1 / 20
2.0
Mediocre

Anonymous,Jul 2025

MEL - SYD

Flight cancelled 2hours before take off after checking in. Booked by airline on flight 6 hours later. No compensation or vouchers till we asked just before the flight took off.
United Airlines
7.4
Good
10,042 reviews
Qantas Airways
7.5
Good
1,067 reviews

Crew

8.1

Entertainment

7.2

Food

7.0

Comfort

7.4

Boarding

7.7

Overall

7.5

Reviews

1 / 20
2.0
Mediocre

Anonymous,Jul 2025

MEL - SYD

Flight cancelled 2hours before take off after checking in. Booked by airline on flight 6 hours later. No compensation or vouchers till we asked just before the flight took off.
American Airlines
7.1
Good
11,837 reviews
Qantas Airways
7.5
Good
1,067 reviews

Crew

8.1

Entertainment

7.2

Food

7.0

Comfort

7.4

Boarding

7.7

Overall

7.5

Reviews

1 / 20
2.0
Mediocre

Anonymous,Jul 2025

MEL - SYD

Flight cancelled 2hours before take off after checking in. Booked by airline on flight 6 hours later. No compensation or vouchers till we asked just before the flight took off.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Sydney. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from St. Louis to Sydney?

    There are many flights that can get you from St. Louis to Sydney in 27h 19m. Fly via Air Canada, United Airlines, or American Airlines to get the fastest option. The distance between St. Louis and Sydney is about 9054 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines flying from St. Louis to Sydney round-trip?

    According to our current data, Qantas Airways ($1,094), United Airlines ($1,144), and American Airlines ($1,233) offers the cheapest pricing from St. Louis to Sydney. Qantas Airways is priced at 23% lower than the current average price of a flight leaving 3 months from now.

  • Can I find deals for flights from St. Louis to Sydney that include hotel bookings?

    Yes. In addition to deals on St. Louis to Sydney flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Sydney?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Sydney.

  • Can I find deals for business class flights from St. Louis to Sydney?

    Yes. Cheapflights offers flight deals from St. Louis to Sydney by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to Sydney?

    Currently, July is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,161). Flying from St. Louis to Sydney in December is currently the most expensive (average of $1,634). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Sydney?

Book flights to Sydney if you plan to visit one of these locations
Parramatta
Wollongong
Coogee
Manly

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for St. Louis to Sydney

See prices for flight routes from nearby airports that may be better suited for you.
Kansas City to Sydney flights

Top 3 airlines flying from St. Louis to Sydney

Discover the top 3 airlines that operate flights from St. Louis to Sydney. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 27, 2026.
AirlineCheapestAverageFlexibilityOn-time
Qantas AirwaysCheapest$1,094Average$1,372FlexibilityNo cancel feeOn-time74%
United AirlinesCheapest$1,144Average$1,381FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$1,233Average$1,497FlexibilityNo cancel feeOn-time71%

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