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Cheap flights from St. Louis to Sydney from $931

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 22/10. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SYD
12 Jun — 19 Jun1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from St. Louis to Sydney

Enter your travel dates to find the best prices.

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 13 May 2026.

Wed 22/719:23
STL
-
SYD
1 stop20h 32m
Air New Zealand
Sun 30/810:20
SYD
-
STL
1 stop23h 19m
Air New Zealand
Deal found 11/5$1,605
Wed 22/719:23
STL
-
SYD
1 stop20h 32m
United Airlines
Sun 2/810:20
SYD
-
STL
1 stop22h 57m
United Airlines
Deal found 11/5$1,606
Wed 21/1006:30
STL
-
SYD
1 stop33h 35m
Qantas Airways
Mon 26/1017:50
SYD
-
STL
2 stops38h 52m
Qantas Airways
Deal found 11/5$1,610
Sun 7/613:38
STL
-
SYD
2 stops26h 22m
Air New Zealand
Sun 14/610:20
SYD
-
STL
1 stop22h 57m
Air New Zealand
Deal found 11/5$1,611
Tue 21/709:15
STL
-
SYD
2 stops30h 45m
United Airlines
Sun 30/810:20
SYD
-
STL
2 stops25h 42m
United Airlines
Deal found 11/5$1,613
Wed 22/705:10
STL
-
SYD
2 stops34h 50m
United Airlines
Wed 29/710:20
SYD
-
STL
2 stops26h 06m
United Airlines
Deal found 11/5$1,632
Wed 22/719:23
STL
-
SYD
1 stop20h 32m
Air New Zealand
Fri 31/710:20
SYD
-
STL
1 stop22h 57m
Air New Zealand
Deal found 11/5$1,674
Wed 22/719:23
STL
-
SYD
1 stop20h 32m
United Airlines
Thu 27/810:20
SYD
-
STL
1 stop23h 19m
United Airlines
Deal found 11/5$1,675
Sun 17/507:05
STL
-
SYD
2 stops33h 15m
Air Canada
Sun 24/509:20
SYD
-
STL
2 stops22h 13m
Air Canada
Deal found 10/5$1,678
Tue 21/709:15
STL
-
SYD
2 stops30h 45m
United Airlines
Fri 28/810:20
SYD
-
STL
1 stop23h 19m
United Airlines
Deal found 11/5$1,682
Wed 22/705:10
STL
-
SYD
2 stops34h 50m
United Airlines
Thu 30/709:30
SYD
-
STL
2 stops22h 03m
United Airlines
Deal found 11/5$1,701

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 13 May 2026.

Round-trip from

$1,605

One-way from

$931

Popular in

December

Cheapest in

March

Average price

$1,855
Air New Zealand
  • Air New Zealand
  • 22/7-30/8
  • 2 total stops
  • 43h 51m total
  • St. Louis to Sydney
Search Deals
22/10
  • 22/10
  • 2 total stops
  • 43h 20m total
  • St. Louis to Sydney
Search Deals
Highest demand for flights based on searches. 3% potential increase in price ($86 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($52 potential savings vs. average return price).
Search Deals
Average for round-trip flights in May 2026
Search Deals

Cheapflights Fare Finder

 
Customise 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 647,157 searches. Data last updated 13 May 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 return flight
Fastest return journey

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 1/8

19:23-06:55

1 stop20h 32m

Sydney Kingsford Smith

Fri 14/8

10:20-18:39

1 stop23h 19m

$1,744

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 13/6

19:23-06:55

1 stop20h 32m

Sydney Kingsford Smith

Sat 27/6

09:30-18:13

2 stops23h 43m

$1,751

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 22/7

14:30-06:50

2 stops25h 20m

Sydney Kingsford Smith

Wed 29/7

09:15-23:22

2 stops29h 07m

$1,851

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 7/9

15:35-06:55

1 stop24h 20m

Sydney Kingsford Smith

Mon 14/9

12:00-18:14

1 stop21h 14m

$2,017

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 13/6

06:35-07:05

1 stop33h 30m

Sydney Kingsford Smith

Sat 27/6

09:10-23:56

1 stop29h 46m

$2,302

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 23/7

19:23-06:55

1 stop20h 32m

Sydney Kingsford Smith

Tue 1/9

10:20-15:38

2 stops44h 18m

$2,360

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 7/11

13:20-08:15

2 stops25h 55m

Sydney Kingsford Smith

Sat 14/11

10:20-19:27

3 stops26h 07m

$2,444

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 26/8

13:36-08:45

3 stops28h 09m

Sydney Kingsford Smith

Sat 12/9

11:55-23:50

3 stops26h 55m

$2,488

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 23/9

13:36-10:40

3 stops30h 04m

Sydney Kingsford Smith

Wed 7/10

11:55-23:45

3 stops27h 50m

$2,627

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 22/7

13:13-10:40

3 stops30h 27m

Sydney Kingsford Smith

Wed 29/7

11:55-08:34

3 stops35h 39m

$2,791

Flights are sorted by cheapest return flights first.

Deals found on 12/5

Showing 1-10 of 14 resultsSorted by cheapest first
1
2

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 return 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, March is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,705). Flying from St. Louis to Sydney in December is currently the most expensive (average of $2,304). 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 for a return flight from St. Louis to Sydney?

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?

    A quick flight from St. Louis to Sydney can take about 20h 32m. United Airlines provides one of the quickest options available for as low as $1,744. There are 14571 km between St. Louis and Sydney. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

  • 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 holiday 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, March is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,705). Flying from St. Louis to Sydney in December is currently the most expensive (average of $2,304). 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

Travelling to a place near Sydney?

Book flights to Sydney if you plan to visit one of these locations
Parramatta
Wollongong
Penrith
Katoomba
Terrigal
Lithgow
Manly
Cronulla
Bondi Beach
Leura
Randwick
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

Fly with Cheapflights

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How does Cheapflights help users find flights from St. Louis to Sydney?

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Why should you use Cheapflights to find cheap flight tickets from St. Louis to Sydney?

By finding flights from multiple airlines and providers at completely no cost, Cheapflights helps millions of users like you annually find the best flights to Sydney from St. Louis.

Can Cheapflights find flights from St. Louis to Sydney with no change fees?

Need flexible booking options for your flight to Sydney from St. Louis? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from St. Louis to Sydney become cheaper?

Yes! Start tracking prices for St. Louis to Sydney flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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