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Cheap flights from St. Louis to Sydney from $673

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Sydney departing on 3/2. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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0 bags

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Find the cheapest flights from St. Louis to Sydney

Cheap round-trip flights

Enter your travel dates to find the best prices.
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
51h 20m
2 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
25h 45m
2 stops
$958Air Canada
Sat, May 2 - Tue, May 12
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
51h 20m
3 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
25h 45m
2 stops
$967Air Canada
Sat, May 2 - Tue, May 12
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
51h 20m
3 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
49h 45m
3 stops
$1,021Air Canada
Sat, May 2 - Tue, May 12
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
51h 20m
2 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
25h 45m
2 stops
$1,025Air Canada
Fri, May 1 - Thu, May 14
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
51h 20m
3 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
25h 45m
2 stops
$1,034Air Canada
Fri, May 1 - Thu, May 14
Qantas Airways Logo
4:13 pm - 8:50 pm
STL
-
SYD
36h 37m
2 stops
Qantas Airways Logo
11:20 am - 11:58 pm
SYD
-
STL
28h 38m
1 stop
$1,043Qantas Airways
Thu, Mar 19 - Wed, Mar 25
Air Canada Logo
6:00 pm - 9:35 am
STL
-
SYD
46h 35m
2 stops
Air Canada Logo
11:20 am - 1:19 pm
SYD
-
STL
42h 59m
2 stops
$1,073Air Canada
Wed, Feb 25 - Wed, Mar 4
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
27h 20m
2 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
25h 45m
2 stops
$1,081Air Canada
Mon, May 4 - Mon, May 18
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
51h 20m
2 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
25h 45m
2 stops
$1,084Air Canada
Mon, May 4 - Mon, May 18
Air Canada Logo
1:00 pm - 7:20 am
STL
-
SYD
51h 20m
3 stops
Air Canada Logo
9:20 am - 8:05 pm
SYD
-
STL
49h 45m
3 stops
$1,089Air Canada
Fri, May 1 - Thu, May 14

United Airlines flights from St. Louis to Sydney

Our best United Airlines deals on St. Louis to Sydney flight tickets
United Airlines
Mar 19
STL4:47 pmLambert-St Louis
22h 13m
1 stop
SYD7:00 amSydney Kingsford Smith
Mar 25
SYD11:50 amSydney Kingsford Smith
20h 15m
1 stop
STL4:05 pmLambert-St Louis
$1,185
United Airlines
Feb 22
STL1:11 pmLambert-St Louis
24h 49m
2 stops
SYD7:00 amSydney Kingsford Smith
Mar 9
SYD11:50 amSydney Kingsford Smith
20h 15m
1 stop
STL4:05 pmLambert-St Louis
$1,186
United Airlines
Mar 4
STL4:28 pmLambert-St Louis
21h 32m
1 stop
SYD7:00 amSydney Kingsford Smith
Mar 10
SYD2:00 pmSydney Kingsford Smith
25h 34m
2 stops
STL11:34 pmLambert-St Louis
$1,190

Turkish Airlines flights from St. Louis to Sydney

Our best Turkish Airlines deals on St. Louis to Sydney flight tickets
Turkish Airlines
Feb 28
STL7:41 amLambert-St Louis
42h 39m
3 stops
SYD7:20 pmSydney Kingsford Smith
Mar 8
SYD9:15 pmSydney Kingsford Smith
63h 52m
3 stops
STL9:07 pmLambert-St Louis
$1,876
Turkish Airlines
Feb 25
STL7:41 amLambert-St Louis
66h 39m
3 stops
SYD7:20 pmSydney Kingsford Smith
Mar 4
SYD9:15 pmSydney Kingsford Smith
64h 52m
3 stops
STL9:07 pmLambert-St Louis
$1,892

momondo 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, momondo users made 832,500 searches. Data last updated February 21, 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

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 5/2

1:00 pm-7:20 am

2 stops51h 20m

Sydney Kingsford Smith

Tue 5/12

9:20 am-8:05 pm

2 stops25h 45m

$958

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 5/2

1:00 pm-7:20 am

3 stops51h 20m

Sydney Kingsford Smith

Tue 5/12

9:20 am-8:05 pm

2 stops25h 45m

$967

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 5/2

1:00 pm-7:20 am

3 stops51h 20m

Sydney Kingsford Smith

Tue 5/12

9:20 am-8:05 pm

3 stops49h 45m

$1,021

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Fri 5/1

1:00 pm-7:20 am

2 stops51h 20m

Sydney Kingsford Smith

Thu 5/14

9:20 am-8:05 pm

2 stops25h 45m

$1,025

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Fri 5/1

1:00 pm-7:20 am

3 stops51h 20m

Sydney Kingsford Smith

Thu 5/14

9:20 am-8:05 pm

2 stops25h 45m

$1,034

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 3/19

4:13 pm-8:50 pm

2 stops36h 37m

Sydney Kingsford Smith

Wed 3/25

11:20 am-11:58 pm

1 stop28h 38m

$1,043

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Wed 2/25

6:00 pm-9:35 am

2 stops46h 35m

Sydney Kingsford Smith

Wed 3/4

11:20 am-1:19 pm

2 stops42h 59m

$1,073

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 5/4

1:00 pm-7:20 am

2 stops27h 20m

Sydney Kingsford Smith

Mon 5/18

9:20 am-8:05 pm

2 stops25h 45m

$1,081

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 5/4

1:00 pm-7:20 am

2 stops51h 20m

Sydney Kingsford Smith

Mon 5/18

9:20 am-8:05 pm

2 stops25h 45m

$1,084

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Fri 5/1

1:00 pm-7:20 am

3 stops51h 20m

Sydney Kingsford Smith

Thu 5/14

9:20 am-8:05 pm

3 stops49h 45m

$1,089

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 17 resultsSorted by cheapest first
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How to get the cheapest flight ticket from St. Louis to Sydney

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the typical price of a round-trip flight between St. Louis and Sydney?

What is the cheapest month to fly to Sydney?

In general, August is the cheapest month to fly from St. Louis to Sydney. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $1,275. If you are unable to visit Sydney during the month of August, then departing from St. Louis during the month March is also very affordable. Most momondo users find prices during this month for around $1,299.

Can stopping save me money on St. Louis to Sydney flights?

You could potentially save up to 22% on your flight if you consider stops on a St. Louis to Sydney flight.

How have St. Louis to Sydney flight prices changed over time?

When to book flights from St. Louis to Sydney

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Sydney according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to Sydney (STL to SYD) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Sydney

Fastest flight time

21h 42m

Direct flights

None
The fastest flight from St. Louis to Sydney takes 21h 42m
There are no direct flights from St. Louis to Sydney. There are no popular flight routes from St. Louis to Sydney.
Search flight deals

  • How far is Lambert-St Louis to Sydney Kingsford Smith by plane?

    Lambert-St Louis and Sydney Kingsford Smith are 9057.2 mi apart from one another. A reasonable flight in good conditions will take 21h 42m.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to Sydney Kingsford Smith Airport?

    Prices for flights from Lambert-St Louis Airport to Sydney Kingsford Smith Airport are updated daily.

  • How many operators does momondo search for flights from Lambert-St Louis Airport to Sydney Kingsford Smith Airport?

  • How old do you have to be to fly from Lambert-St Louis Airport to Sydney Kingsford Smith Airport?

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Sydney Kingsford Smith Airport.

  • What documentation or ID do you need to fly to Sydney Kingsford Smith Airport?

    The travel and health documents you'll need for your trip to Sydney Kingsford Smith Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Sydney Kingsford Smith Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

  • What is the most popular airline from St. Louis to Sydney?

Best airlines flying from St. Louis to Sydney

Compare and see reviews for airlines that fly from St. Louis to Sydney with momondo
Airline
Rating
Free Cancellation
Price
Air CanadaPriceFrom $608Free CancellationRating
7.1
10,734 reviews
Search Air Canada flights
Fiji AirwaysPriceFrom $1,132Free CancellationRating
8.0
226 reviews
Search Fiji Airways flights
Qantas AirwaysPriceFrom $1,145Free CancellationRating
7.5
995 reviews
Search Qantas Airways flights
United AirlinesPriceFrom $1,211Free CancellationRating
7.4
9,336 reviews
Search United Airlines flights
American AirlinesPriceFrom $1,233Free CancellationRating
7.2
11,335 reviews
Search American Airlines flights

Traveling to a place near Sydney?

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

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Sydney?

It is quick and easy to find St. Louis to Sydney flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Sydney that suits you.

Can I find flights from St. Louis to Sydney with flexible booking policies on momondo?

Yes. All flights to Sydney from St. Louis on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from St. Louis to Sydney?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Sydney from St. Louis.

I’m not ready to book a flight from St. Louis to Sydney right now. Can momondo alert me if prices change?

If you are not ready to book a flight from St. Louis to Sydney now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Sydney and let you know when they change.

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