What is the cheapest airline that flies from Lambert-St Louis to Sydney Kingsford Smith?

Qantas Airways and American Airlines are the most popular carriers operating from Lambert-St Louis to Sydney Kingsford Smith

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 refresh daily.

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

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and stopovers. It is recommended that you verify 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 required travel and health documents for your Sydney Kingsford Smith Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's licence and a passport valid for six months after your intended arrival at Sydney Kingsford Smith Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

$821 Cheap Flights from St. Louis to Sydney in 2026

1 adult

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16:13 - 20:50

STL

SYD

36h 37m

2 stops

11:20 - 23:58

SYD

STL

28h 38m

1 stop

$1,394Qantas Airways

Sun, 15 Mar - Tue, 24 Mar

18:50 - 20:50

STL

SYD

34h 00m

2 stops

11:20 - 23:58

SYD

STL

28h 38m

1 stop

$1,395Qantas Airways

Mon, 9 Mar - Mon, 16 Mar

06:38 - 07:35

STL

SYD

55h 57m

2 stops

17:45 - 23:59

SYD

STL

23h 14m

1 stop

$1,421Qantas Airways

Sat, 21 Feb - Sat, 28 Feb

16:13 - 07:35

STL

SYD

46h 22m

2 stops

11:20 - 23:58

SYD

STL

28h 38m

1 stop

$1,476Qantas Airways

Sat, 7 Mar - Sat, 14 Mar

16:13 - 06:55

STL

SYD

22h 42m

1 stop

13:05 - 19:29

SYD

STL

22h 24m

1 stop

$1,621Qantas Airways

Mon, 9 Mar - Mon, 16 Mar

06:38 - 20:50

STL

SYD

45h 12m

2 stops

17:45 - 23:59

SYD

STL

23h 14m

1 stop

$1,633Qantas Airways

Thu, 26 Feb - Thu, 5 Mar

06:38 - 20:50

STL

SYD

45h 12m

2 stops

17:45 - 23:59

SYD

STL

23h 14m

1 stop

$1,635Qantas Airways

Thu, 26 Feb - Thu, 5 Mar

16:13 - 06:55

STL

SYD

21h 42m

1 stop

14:05 - 17:13

SYD

STL

20h 08m

1 stop

$1,680Qantas Airways

Sun, 22 Feb - Fri, 6 Mar

18:05 - 07:20

STL

SYD

46h 15m

2 stops

09:20 - 16:56

SYD

STL

46h 36m

2 stops

$1,698Air Canada

Fri, 10 Apr - Tue, 14 Apr

08:54 - 07:20

STL

SYD

31h 26m

2 stops

09:20 - 16:56

SYD

STL

46h 36m

2 stops

$1,709Air Canada

Sun, 5 Apr - Tue, 14 Apr

United Airlines flights from St. Louis to Sydney

Our best United Airlines deals on St. Louis to Sydney flight tickets

United Airlines

4 May

STL08:30Lambert-St Louis

31h 25m

1 stop

SYD06:55Sydney Kingsford Smith

18 May

SYD10:20Sydney Kingsford Smith

23h 02m

1 stop

STL18:22Lambert-St Louis

$1,825

United Airlines

14 Feb

STL16:30Lambert-St Louis

47h 35m

2 stops

SYD09:05Sydney Kingsford Smith

18 Feb

SYD12:10Sydney Kingsford Smith

21h 34m

1 stop

STL16:44Lambert-St Louis

$1,852

United Airlines

14 Feb

STL16:30Lambert-St Louis

47h 35m

2 stops

SYD09:05Sydney Kingsford Smith

18 Feb

SYD12:10Sydney Kingsford Smith

22h 34m

2 stops

STL17:44Lambert-St Louis

$1,855

American Airlines flights from St. Louis to Sydney

Our best American Airlines deals on St. Louis to Sydney flight tickets

American Airlines

15 Mar

STL11:46Lambert-St Louis

27h 09m

1 stop

SYD06:55Sydney Kingsford Smith

24 Mar

SYD11:20Sydney Kingsford Smith

28h 38m

1 stop

STL23:58Lambert-St Louis

$1,800

American Airlines

15 Mar

STL11:46Lambert-St Louis

27h 09m

1 stop

SYD06:55Sydney Kingsford Smith

24 Mar

SYD11:20Sydney Kingsford Smith

28h 38m

1 stop

STL23:58Lambert-St Louis

$1,802

American Airlines

4 Mar

STL06:38Lambert-St Louis

31h 47m

1 stop

SYD07:25Sydney Kingsford Smith

10 Mar

SYD11:20Sydney Kingsford Smith

28h 38m

1 stop

STL23:58Lambert-St Louis

$1,805

Fly from

Fly to

Route

Depart

Return

Price

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sun 15/3

16:13-20:50

2 stops36h 37m

Sydney Kingsford Smith

Tue 24/3

11:20-23:58

1 stop28h 38m

$1,394

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 9/3

18:50-20:50

2 stops34h 00m

Sydney Kingsford Smith

Mon 16/3

11:20-23:58

1 stop28h 38m

$1,395

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 21/2

06:38-07:35

2 stops55h 57m

Sydney Kingsford Smith

Sat 28/2

17:45-23:59

1 stop23h 14m

$1,421

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sat 7/3

16:13-07:35

2 stops46h 22m

Sydney Kingsford Smith

Sat 14/3

11:20-23:58

1 stop28h 38m

$1,476

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Mon 9/3

16:13-06:55

1 stop22h 42m

Sydney Kingsford Smith

Mon 16/3

13:05-19:29

1 stop22h 24m

$1,621

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 26/2

06:38-20:50

2 stops45h 12m

Sydney Kingsford Smith

Thu 5/3

17:45-23:59

1 stop23h 14m

$1,633

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Thu 26/2

06:38-20:50

2 stops45h 12m

Sydney Kingsford Smith

Thu 5/3

17:45-23:59

1 stop23h 14m

$1,635

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sun 22/2

16:13-06:55

1 stop21h 42m

Sydney Kingsford Smith

Fri 6/3

14:05-17:13

1 stop20h 08m

$1,680

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Fri 10/4

18:05-07:20

2 stops46h 15m

Sydney Kingsford Smith

Tue 14/4

09:20-16:56

2 stops46h 36m

$1,698

St. LouisSydney

STL - SYD

STLSYD

Lambert-St Louis

Sun 5/4

08:54-07:20

2 stops31h 26m

Sydney Kingsford Smith

Tue 14/4

09:20-16:56

2 stops46h 36m

$1,709

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

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

Prices

Airlines

What is the cheapest month to fly to Sydney?

The month of August is, on average, the cheapest month to fly to Sydney from St. Louis, with most prices found around $1,720. If you aren’t able to travel to Sydney during the month of August, then flying in November is also cheap. Prices for this month can be found on momondo for an average of $1,919.

How far in advance should I book a flight to Sydney?

You are more likely to see cheaper flights to Sydney from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Sydney for around $2,050 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Sydney from St. Louis for as low as $1,354 on momondo.

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 return 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	20h 35m
Direct flights	None

The fastest flight from St. Louis to Sydney takes 20h 35m

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?
A flight from Lambert-St Louis to Sydney Kingsford Smith will travel around 14576.1 km. In terms of flight time, this usually takes a little over 20h 35m.
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 refresh daily.
How old do you have to be to fly from Lambert-St Louis Airport to Sydney Kingsford Smith Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and stopovers. It is recommended that you verify 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 required travel and health documents for your Sydney Kingsford Smith Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's licence and a passport valid for six months after your intended arrival at Sydney Kingsford Smith Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

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Wollongong

Terrigal

Penrith

Katoomba

Lithgow

Leura

Manly

Coogee

Bondi Beach

Cronulla

Randwick

Charlestown

Newport

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?

momondo does allow users to show only those flights to Sydney from St. Louis which offer a flexible booking policy as well as other useful filters and features.

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

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from St. Louis to Sydney.

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 simply researching potential flights to Sydney, momondo offers a useful price alert feature which will track prices for flights to Sydney from St. Louis and alert you when they change.