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$545+ 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 3/2. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SYD
nov. 27 — dic. 41
jue. 11/27
jue. 12/4
1 adult, Economy
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1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

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Cheapflights Tip: The best prices from Lambert-St Louis to Sydney Kingsford Smith are usually found in August or October, booked 57 days in advance, depart on a Wednesday or Tuesday and return on a Wednesday

Cheap 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 octubre 28, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$1,241
(oojo)

One-way from

$545
(FlightHub)

Popular in

December

Cheapest in

August

Average price

$1,331
Provider with most accurate pricing for Lambert-St Louis-Sydney Kingsford Smith flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Sydney Kingsford Smith flights.
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From Lambert-St Louis to Sydney Kingsford Smith
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One-way flight from Lambert-St Louis to Sydney Kingsford Smith
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Highest demand for flights based on searches. 6% potential increase in price ($94 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($29 potential savings vs. average RT price).
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Average for round-trip flights in October 2025
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Find 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 octubre 28, 2025.

This Expedia deal was found by Cheapflights users on 10/26. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/274:43 pmSTL - SYD
2 stops47h 57mAir Canada
lun. 11/1011:20 amSYD - STL
2 stops27h 34mAir Canada
Deal found 10/26$1,219
This oojo deal was found by Cheapflights users on 10/27. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/127:00 amSTL - SYD
2 stops45h 55mQantas Airways
dom. 11/232:05 pmSYD - STL
1 stop19h 27mQantas Airways
Deal found 10/27$1,241
This Qantas Airways deal was found by Cheapflights users on 10/28. 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 Qantas Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/1211:42 amSTL - SYD
1 stop26h 13mMultiple Airlines
dom. 11/232:05 pmSYD - STL
1 stop19h 27mMultiple Airlines
Deal found 10/28$1,247
This American Airlines deal was found by Cheapflights users on 10/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/57:00 amSTL - SYD
1 stop31h 25mAmerican Airlines
dom. 11/232:05 pmSYD - STL
1 stop22h 25mAmerican Airlines
Deal found 10/28$1,248
This oojo deal was found by Cheapflights users on 10/25. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/105:30 pmSTL - SYD
1 stop20h 25mQantas Airways
mié. 12/177:05 amSYD - STL
2 stops29h 24mQantas Airways
Deal found 10/25$1,254
This American Airlines deal was found by Cheapflights users on 10/26. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/276:39 amSTL - SYD
1 stop34h 21mAmerican Airlines
lun. 11/1011:20 amSYD - STL
2 stops25h 07mAmerican Airlines
Deal found 10/26$1,268
This Qantas Airways deal was found by Cheapflights users on 10/27. 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 Qantas Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/51:20 pmSTL - SYD
1 stop24h 35mQantas Airways
dom. 11/232:05 pmSYD - STL
1 stop19h 27mQantas Airways
Deal found 10/27$1,275
This United Airlines deal was found by Cheapflights users on 10/28. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 11/25:29 pmSTL - SYD
1 stop22h 46mUnited Airlines
dom. 11/1611:50 amSYD - STL
1 stop23h 57mUnited Airlines
Deal found 10/28$1,287
This American Airlines deal was found by Cheapflights users on 10/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 11/283:59 pmSTL - SYD
1 stop21h 56mAmerican Airlines
dom. 12/142:05 pmSYD - STL
1 stop25h 20mAmerican Airlines
Deal found 10/28$1,298

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 octubre 28, 2025.
Use the filters below to find and compare flights from St. Louis to Sydney that are best for you.

Fly from

St. Louis

Fly to

Sydney

Route

Depart

Return

Price

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

mar. 2/10

4:15 pm-9:35 am

2 stops48h 20m

Sydney Kingsford Smith

vie. 2/27

11:20 am-8:26 pm

2 stops26h 06m

$1,194

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

vie. 11/28

7:00 am-9:20 am

2 stops33h 20m

Sydney Kingsford Smith

dom. 12/14

2:05 pm-7:27 pm

1 stop22h 22m

$1,241

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

mié. 11/12

11:42 am-6:55 am

1 stop26h 13m

Sydney Kingsford Smith

dom. 11/23

2:05 pm-4:32 pm

1 stop19h 27m

$1,247

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

jue. 1/29

2:38 pm-9:00 am

2 stops25h 22m

Sydney Kingsford Smith

mié. 2/18

11:20 am-5:05 pm

2 stops22h 45m

$1,301

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

dom. 4/19

2:33 pm-7:30 am

2 stops25h 57m

Sydney Kingsford Smith

sáb. 4/25

9:10 am-11:16 pm

1 stop29h 06m

$1,301

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

jue. 2/12

6:50 pm-10:05 pm

2 stops34h 15m

Sydney Kingsford Smith

mar. 2/17

2:00 pm-11:21 pm

2 stops26h 21m

$1,315

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

mar. 2/10

2:38 pm-9:00 am

2 stops25h 22m

Sydney Kingsford Smith

vie. 2/27

2:05 pm-5:05 pm

1 stop20h 00m

$1,329

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

sáb. 1/17

1:40 pm-9:00 am

2 stops26h 20m

Sydney Kingsford Smith

sáb. 1/24

2:05 pm-7:51 pm

1 stop22h 46m

$1,351

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

sáb. 4/4

4:05 pm-7:20 am

2 stops48h 15m

$671

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

mié. 12/24

5:19 pm-12:30 pm

3 stops50h 11m

$759

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/26

Showing 1-10 of 15 results
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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 October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
AranGrantPrice Accuracy2 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
oojoPrice Accuracy3 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 eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on St. Louis-Sydney flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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

How far ahead should I book a flight from St. Louis to Sydney?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Sydney. Price data was last updated on October 24, 2025.

The best time to book flights from St. Louis to Sydney is 57 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

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

Currently, August is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $693). Flying from St. Louis to Sydney in February is currently the most expensive (average of $1,270). 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.

What is the cheapest time of day to fly from STL to SYD?

Find hourly flight availability from St. Louis to Sydney. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated octubre 28, 2025.

It’s optimal to fly from St. Louis to Sydney in the evening. By choosing this option you can save up to 23% on the cost of your flight, compared to a flight at noon.

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 octubre 28, 2025.
Get a feel of what it's like to fly with Fiji Airways, Qantas Airways, and United 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.
Fiji Airways
8.0
Very good
207 reviews

Boarding

8.1

Overall

8.0

Comfort

8.0

Food

7.5

Entertainment

7.4

Crew

8.5

Reviews

1 / 16
6.0
Good

Christopher,Jun 2025

LAX - NAN

No attempt to make you comfortable. All they care about is how can they pack more people on the plane and how can they charge you for as much as possible. I find it invasive and discriminatory that you weigh my carryon (or any of my naggage frankly). If I physically weighed 15kilos more and my bag weighed under your stupid and arbitrary weight limit I would not be charged... but if I'm a person who is skinny and weighs less, well heaven forbid my bag is 1 kilo heavier than you wish!! $$$ VERY VERY DISCRIMINATORY POLICY!! NEXT TIME I'LL TRY TO EAT MY BAGGAGE SO THAT I CAN TAKE ON AS MUCH WEIGHT AS I WANT! Yeah... sounds ridiculous doesn't it!? No more ridiculous than you charging more for people who bring more baggage weight while letting obese people carry on all the weight they want! It just proves it has absolutely nothing to do with safety, or even your operating costs... Just squeezing as much money out of us as possible!!
Fiji Airways
8.0
Very good
207 reviews
Fiji Airways
8.0
Very good
207 reviews

Boarding

8.1

Overall

8.0

Comfort

8.0

Food

7.5

Entertainment

7.4

Crew

8.5

Reviews

1 / 16
6.0
Good

Christopher,Jun 2025

LAX - NAN

No attempt to make you comfortable. All they care about is how can they pack more people on the plane and how can they charge you for as much as possible. I find it invasive and discriminatory that you weigh my carryon (or any of my naggage frankly). If I physically weighed 15kilos more and my bag weighed under your stupid and arbitrary weight limit I would not be charged... but if I'm a person who is skinny and weighs less, well heaven forbid my bag is 1 kilo heavier than you wish!! $$$ VERY VERY DISCRIMINATORY POLICY!! NEXT TIME I'LL TRY TO EAT MY BAGGAGE SO THAT I CAN TAKE ON AS MUCH WEIGHT AS I WANT! Yeah... sounds ridiculous doesn't it!? No more ridiculous than you charging more for people who bring more baggage weight while letting obese people carry on all the weight they want! It just proves it has absolutely nothing to do with safety, or even your operating costs... Just squeezing as much money out of us as possible!!
Qantas Airways
7.5
Good
924 reviews
Fiji Airways
8.0
Very good
207 reviews

Boarding

8.1

Overall

8.0

Comfort

8.0

Food

7.5

Entertainment

7.4

Crew

8.5

Reviews

1 / 16
6.0
Good

Christopher,Jun 2025

LAX - NAN

No attempt to make you comfortable. All they care about is how can they pack more people on the plane and how can they charge you for as much as possible. I find it invasive and discriminatory that you weigh my carryon (or any of my naggage frankly). If I physically weighed 15kilos more and my bag weighed under your stupid and arbitrary weight limit I would not be charged... but if I'm a person who is skinny and weighs less, well heaven forbid my bag is 1 kilo heavier than you wish!! $$$ VERY VERY DISCRIMINATORY POLICY!! NEXT TIME I'LL TRY TO EAT MY BAGGAGE SO THAT I CAN TAKE ON AS MUCH WEIGHT AS I WANT! Yeah... sounds ridiculous doesn't it!? No more ridiculous than you charging more for people who bring more baggage weight while letting obese people carry on all the weight they want! It just proves it has absolutely nothing to do with safety, or even your operating costs... Just squeezing as much money out of us as possible!!
United Airlines
7.4
Good
8,996 reviews
Fiji Airways
8.0
Very good
207 reviews

Boarding

8.1

Overall

8.0

Comfort

8.0

Food

7.5

Entertainment

7.4

Crew

8.5

Reviews

1 / 16
6.0
Good

Christopher,Jun 2025

LAX - NAN

No attempt to make you comfortable. All they care about is how can they pack more people on the plane and how can they charge you for as much as possible. I find it invasive and discriminatory that you weigh my carryon (or any of my naggage frankly). If I physically weighed 15kilos more and my bag weighed under your stupid and arbitrary weight limit I would not be charged... but if I'm a person who is skinny and weighs less, well heaven forbid my bag is 1 kilo heavier than you wish!! $$$ VERY VERY DISCRIMINATORY POLICY!! NEXT TIME I'LL TRY TO EAT MY BAGGAGE SO THAT I CAN TAKE ON AS MUCH WEIGHT AS I WANT! Yeah... sounds ridiculous doesn't it!? No more ridiculous than you charging more for people who bring more baggage weight while letting obese people carry on all the weight they want! It just proves it has absolutely nothing to do with safety, or even your operating costs... Just squeezing as much money out of us as possible!!
American Airlines
7.2
Good
11,034 reviews
Fiji Airways
8.0
Very good
207 reviews

Boarding

8.1

Overall

8.0

Comfort

8.0

Food

7.5

Entertainment

7.4

Crew

8.5

Reviews

1 / 16
6.0
Good

Christopher,Jun 2025

LAX - NAN

No attempt to make you comfortable. All they care about is how can they pack more people on the plane and how can they charge you for as much as possible. I find it invasive and discriminatory that you weigh my carryon (or any of my naggage frankly). If I physically weighed 15kilos more and my bag weighed under your stupid and arbitrary weight limit I would not be charged... but if I'm a person who is skinny and weighs less, well heaven forbid my bag is 1 kilo heavier than you wish!! $$$ VERY VERY DISCRIMINATORY POLICY!! NEXT TIME I'LL TRY TO EAT MY BAGGAGE SO THAT I CAN TAKE ON AS MUCH WEIGHT AS I WANT! Yeah... sounds ridiculous doesn't it!? No more ridiculous than you charging more for people who bring more baggage weight while letting obese people carry on all the weight they want! It just proves it has absolutely nothing to do with safety, or even your operating costs... Just squeezing as much money out of us as possible!!
Air Canada
7.1
Good
10,370 reviews
Fiji Airways
8.0
Very good
207 reviews

Boarding

8.1

Overall

8.0

Comfort

8.0

Food

7.5

Entertainment

7.4

Crew

8.5

Reviews

1 / 16
6.0
Good

Christopher,Jun 2025

LAX - NAN

No attempt to make you comfortable. All they care about is how can they pack more people on the plane and how can they charge you for as much as possible. I find it invasive and discriminatory that you weigh my carryon (or any of my naggage frankly). If I physically weighed 15kilos more and my bag weighed under your stupid and arbitrary weight limit I would not be charged... but if I'm a person who is skinny and weighs less, well heaven forbid my bag is 1 kilo heavier than you wish!! $$$ VERY VERY DISCRIMINATORY POLICY!! NEXT TIME I'LL TRY TO EAT MY BAGGAGE SO THAT I CAN TAKE ON AS MUCH WEIGHT AS I WANT! Yeah... sounds ridiculous doesn't it!? No more ridiculous than you charging more for people who bring more baggage weight while letting obese people carry on all the weight they want! It just proves it has absolutely nothing to do with safety, or even your operating costs... Just squeezing as much money out of us as possible!!

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 33h 20m. Fly via Air Canada or Qantas Airways 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, Air Canada ($897), Fiji Airways ($1,132), and United Airlines ($1,209) offers the cheapest pricing from St. Louis to Sydney. Air Canada is priced at 38% 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, August is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $693). Flying from St. Louis to Sydney in February is currently the most expensive (average of $1,270). 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
Manly
Coogee

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
Columbia to Sydney flights
Springfield to Coolangatta flights

Top 5 airlines flying from St. Louis to Sydney

Discover the top 5 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 octubre 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air CanadaCheapest$897Average$1,281FlexibilityNo cancel feeOn-time67%
Fiji AirwaysCheapest$1,132Average$1,222FlexibilityNo cancel feeOn-time74%
United AirlinesCheapest$1,209Average$1,510FlexibilityNo cancel feeOn-time69%
Qantas AirwaysCheapest$1,262Average$1,515FlexibilityNo cancel feeOn-time74%
American AirlinesCheapest$1,344Average$1,495FlexibilityNo cancel feeOn-time71%

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