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Cheap flights from St. Louis to Sydney from $999

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 8/8. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SYD
11 Jul — 18 Jul1
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 11 June 2026.

Mon 16/1107:00
STL
-
SYD
1 stop33h 00m
Qantas Airways
Sat 21/1117:50
SYD
-
STL
2 stops35h 47m
Qantas Airways
Deal found 11/6$1,485
Sun 15/1118:13
STL
-
SYD
2 stops33h 37m
Qantas Airways
Wed 25/1111:15
SYD
-
STL
1 stop29h 27m
Qantas Airways
Deal found 9/6$1,534
Tue 1/1218:13
STL
-
SYD
2 stops33h 37m
Qantas Airways
Tue 15/1211:15
SYD
-
STL
1 stop29h 42m
Qantas Airways
Deal found 9/6$1,676
Mon 8/606:35
STL
-
SYD
1 stop33h 30m
Qantas Airways
Sun 21/609:10
SYD
-
STL
1 stop29h 46m
Qantas Airways
Deal found 7/6$1,865
Mon 8/614:57
STL
-
SYD
2 stops24h 58m
United Airlines
Sun 21/610:20
SYD
-
STL
1 stop22h 57m
United Airlines
Deal found 7/6$1,872
Sun 7/616:48
STL
-
SYD
2 stops23h 12m
United Airlines
Sun 21/610:20
SYD
-
STL
1 stop22h 57m
United Airlines
Deal found 6/6$1,880
Tue 13/1006:30
STL
-
SYD
2 stops41h 00m
Qantas Airways
Wed 18/1118:45
SYD
-
STL
2 stops45h 57m
Qantas Airways
Deal found 9/6$1,893
Tue 13/1006:30
STL
-
SYD
2 stops36h 15m
Qantas Airways
Fri 13/1119:40
SYD
-
STL
2 stops45h 02m
Qantas Airways
Deal found 10/6$1,895
Thu 3/906:00
STL
-
SYD
2 stops40h 55m
Qantas Airways
Thu 17/922:00
SYD
-
STL
2 stops40h 40m
Qantas Airways
Deal found 8/6$1,907
Mon 8/620:14
STL
-
SYD
2 stops43h 51m
American Airlines
Sun 21/609:10
SYD
-
STL
1 stop29h 46m
American Airlines
Deal found 8/6$1,909
Mon 8/619:55
STL
-
SYD
2 stops43h 55m
Delta
Sun 21/609:15
SYD
-
STL
2 stops29h 08m
Delta
Deal found 8/6$1,915

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 11 June 2026.

Round-trip from

$1,534

One-way from

$999

Popular in

December

Cheapest in

January

Average price

$2,224
Qantas Airways
  • Qantas Airways
  • 15/11-25/11
  • 3 total stops
  • 63h 04m total
  • St. Louis to Sydney
Search Deals
Qantas Airways
  • Qantas Airways
  • 8/8
  • 2 total stops
  • 37h 45m total
  • St. Louis to Sydney
Search Deals
Highest demand for flights based on searches. 2% potential increase in price ($75 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($54 potential savings vs. average return price).
Search Deals
Average for round-trip flights in June 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 11 June 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 8/8

19:23-06:55

1 stop20h 32m

Sydney Kingsford Smith

Sun 16/8

10:20-18:39

1 stop23h 19m

$1,969

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 23/9

05:10-07:20

2 stops35h 10m

Sydney Kingsford Smith

Wed 7/10

10:20-12:13

3 stops41h 53m

$2,004

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 23/9

13:36-07:00

2 stops26h 24m

Sydney Kingsford Smith

Wed 7/10

11:20-18:43

1 stop23h 23m

$2,069

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Fri 24/7

05:10-07:00

2 stops34h 50m

Sydney Kingsford Smith

Fri 31/7

09:30-16:33

2 stops22h 03m

$2,069

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 7/9

08:42-06:55

1 stop31h 13m

Sydney Kingsford Smith

Mon 14/9

10:20-18:39

1 stop23h 19m

$2,080

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 22/6

07:08-06:50

2 stops32h 42m

Sydney Kingsford Smith

Thu 25/6

09:15-19:03

2 stops24h 48m

$2,369

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 3/9

12:59-10:40

3 stops30h 41m

Sydney Kingsford Smith

Thu 17/9

11:55-23:40

3 stops26h 45m

$2,848

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 3/9

12:59-08:45

3 stops28h 46m

Sydney Kingsford Smith

Wed 16/9

11:55-23:40

3 stops26h 45m

$2,988

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 16/11

16:17-07:00

1 stop21h 43m

Sydney Kingsford Smith

Sat 21/11

11:50-22:06

1 stop27h 16m

$3,222

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 22/6

13:13-10:40

3 stops30h 27m

Sydney Kingsford Smith

Thu 25/6

11:55-23:57

3 stops27h 02m

$3,955

Flights are sorted by cheapest return flights first.

Deals found on 6/6

Showing 1-10 of 19 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, January is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,758). Flying from St. Louis to Sydney in December is currently the most expensive (average of $2,372). 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 $1,969. 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, January is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,758). Flying from St. Louis to Sydney in December is currently the most expensive (average of $2,372). 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
Cronulla
Manly
Terrigal
Lithgow
Randwick
Bondi Beach
Leura
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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