Cheap flights from St. Louis (STL) to Sydney (SYD) from $1,145

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 6/9. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
STL — SYD
May 17 — May 241

The best prices from Lambert-St Louis to Sydney Kingsford Smith are usually found in February or March, booked 60 days in advance, depart on a Sunday or Saturday and return on a Monday

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 May 12, 2024.

Popular in

December

Cheapest in

February

Average price

$1,551

Round-trip from

$1,110
High demand for flights, 35% potential price rise
Best time to find cheap flights, 22% potential price drop
Average for round-trip flights in May 2024
From Lambert-St Louis to Sydney Kingsford Smith

What is the cheapest day to fly round-trip from St. Louis to Sydney?

It’s generally more expensive to depart on a Saturday, if you have to leave on this day you can still search on Cheapflights to find great options that meet your needs.

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

Find a great deal and save up to 109% by booking at least 61 days prior to your desired departure date, rather than waiting until the week of travel. According to our data, there are a number of flights available from St. Louis to Sydney within the next two weeks, with the cheapest ticket starting at $989.

What is the cheapest month to fly from St. Louis to Sydney?

Flights from St. Louis to Sydney lean towards being more expensive in December. Prices are generally better when you fly from St. Louis to Sydney in February, with the cheapest ticket starting at $1,194.

When is the cheapest time to fly from St. Louis to Sydney (STL - SYD)?

It’s optimal to fly from St. Louis to Sydney in the morning. By choosing this option you can save up to 8% on the cost of your flight, compared to a flight in the evening.

Cheap Air Canada flights from St. Louis to Sydney

Explore cheap flight options specifically provided by Air Canada for the route between St. Louis and Sydney. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 2,633,403 searches. Data last updated May 12, 2024.
Peruse some of the lowest-priced Air Canada flights we've found from St. Louis to Sydney. It's recommended that users confirm their flight details before booking.
Sun 6/911:00 amSTL - SYD
2 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
2 stops50h 45mAir Canada
Deal found 5/12$1,145
Mon 8/512:00 pmSTL - SYD
2 stops28h 20mAir Canada
Sun 8/259:20 amSYD - STL
2 stops25h 41mAir Canada
Deal found 5/11$1,148
Sun 6/911:00 amSTL - SYD
2 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,151
Sat 8/1712:00 pmSTL - SYD
2 stops52h 20mAir Canada
Fri 8/309:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,186
Sat 8/1712:00 pmSTL - SYD
3 stops52h 20mAir Canada
Fri 8/309:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,192
Sun 6/911:00 amSTL - SYD
2 stops53h 20mAir Canada
Sun 6/169:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,261
Sun 6/911:00 amSTL - SYD
3 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,270
Sun 6/911:00 amSTL - SYD
3 stops29h 20mAir Canada
Sun 6/169:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,379
Wed 8/1410:10 amSTL - SYD
2 stops30h 10mAir Canada
Sun 8/189:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/11$1,417

Cheap United Airlines flights from St. Louis to Sydney

Explore cheap flight options specifically provided by United Airlines for the route between St. Louis and Sydney. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 2,633,403 searches. Data last updated May 12, 2024.
Browse through some of the cheapest United Airlines flights traveling from St. Louis to Sydney. Check back soon if you're not seeing flights that suit your needs.
Mon 8/59:08 amSTL - SYD
2 stops30h 52mUnited Airlines
Sun 8/2510:20 amSYD - STL
1 stop21h 43mUnited Airlines
Deal found 5/11$1,389
Sun 9/226:00 pmSTL - SYD
1 stop22h 00mUnited Airlines
Fri 10/410:20 amSYD - STL
1 stop29h 10mUnited Airlines
Deal found 5/11$1,435
Sun 9/221:39 pmSTL - SYD
2 stops26h 21mUnited Airlines
Fri 10/410:20 amSYD - STL
2 stops21h 10mUnited Airlines
Deal found 5/11$1,439
Sat 8/174:36 pmSTL - SYD
2 stops47h 24mUnited Airlines
Fri 8/3010:20 amSYD - STL
1 stop21h 43mUnited Airlines
Deal found 5/12$1,456
Fri 6/214:55 pmSTL - SYD
2 stops23h 00mUnited Airlines
Sat 7/1310:20 amSYD - STL
2 stops26h 57mUnited Airlines
Deal found 5/12$1,489
Sun 6/305:30 pmSTL - SYD
2 stops22h 25mUnited Airlines
Sun 7/79:30 amSYD - STL
2 stops27h 47mUnited Airlines
Deal found 5/12$2,050

Cheap St. Louis to Sydney flights in May & June 2024

Find cheap flight options from St. Louis to Sydney specifically for the months of May and June 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 2,633,403 searches. Prices were last updated on May 12, 2024.
These are some of the best deals we've found on flights to Sydney in 2024 at this time. Check back soon for alternative fares.
Sun 6/911:00 amSTL - SYD
2 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
2 stops50h 45mAir Canada
Deal found 5/12$1,145
Sun 6/911:00 amSTL - SYD
2 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,151
Sun 6/911:00 amSTL - SYD
2 stops53h 20mAir Canada
Sun 6/169:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,261
Sun 6/911:00 amSTL - SYD
3 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,270
Sun 6/911:00 amSTL - SYD
3 stops29h 20mAir Canada
Sun 6/169:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,379
Mon 6/241:10 pmSTL - SYD
2 stops26h 50mUnited Airlines
Wed 7/1010:20 amSYD - STL
2 stops21h 52mUnited Airlines
Deal found 5/11$1,389
Sun 6/96:29 amSTL - SYD
1 stop33h 36mQantas Airways
Sun 6/169:15 amSYD - STL
1 stop28h 43mQantas Airways
Deal found 5/12$1,412
Sun 6/99:23 amSTL - SYD
2 stops30h 42mAmerican Airlines
Sun 6/169:15 amSYD - STL
1 stop28h 43mAmerican Airlines
Deal found 5/12$1,488
Fri 6/213:10 pmSTL - SYD
2 stops24h 50mUnited Airlines
Sat 7/139:30 amSYD - STL
2 stops21h 58mUnited Airlines
Deal found 5/11$1,489

St. Louis to Sydney 2024 flight deals

Discover exclusive flight deals for travel between St. Louis and Sydney in 2024. Find excellent offers based on user searches. Over the last 7 days, Cheapflights users made 2,633,403 searches. Data last updated May 12, 2024.
These are some of the best deals we've found on flights to Sydney in 2024 at this time. Check back soon for alternative fares.
Sun 6/911:00 amSTL - SYD
2 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
2 stops50h 45mAir Canada
Deal found 5/12$1,145
Mon 8/512:00 pmSTL - SYD
2 stops28h 20mAir Canada
Sun 8/259:20 amSYD - STL
2 stops25h 41mAir Canada
Deal found 5/11$1,148
Sun 6/911:00 amSTL - SYD
2 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,151
Wed 10/3010:40 amSTL - SYD
2 stops29h 40mAir Canada
Tue 11/2611:20 amSYD - STL
2 stops39h 33mAir Canada
Deal found 5/11$1,154
Sat 8/1712:00 pmSTL - SYD
2 stops52h 20mAir Canada
Fri 8/309:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,186
Sat 8/1712:00 pmSTL - SYD
3 stops52h 20mAir Canada
Fri 8/309:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,192
Sun 6/911:00 amSTL - SYD
2 stops53h 20mAir Canada
Sun 6/169:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,261
Sun 6/911:00 amSTL - SYD
3 stops29h 20mAir Canada
Mon 7/299:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/12$1,270
Sun 6/911:00 amSTL - SYD
3 stops29h 20mAir Canada
Sun 6/169:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/12$1,379

Find flights from St. Louis to Sydney within your budget

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 2,633,403 searches. Data last updated May 12, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$1,145 - $1,534

Route

Depart

Return

Price

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Sun 6/9

2 stops29h 20m

Sydney Kingsford Smith

Mon 7/29

2 stops50h 45m

$1,145

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Mon 8/5

2 stops28h 20m

Sydney Kingsford Smith

Sun 8/25

2 stops25h 41m

$1,148

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Sun 6/9

2 stops29h 20m

Sydney Kingsford Smith

Mon 7/29

3 stops50h 45m

$1,151

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Sat 8/17

2 stops52h 20m

Sydney Kingsford Smith

Fri 8/30

2 stops45h 01m

$1,186

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Mon 8/5

2 stops30h 52m

Sydney Kingsford Smith

Sun 8/25

1 stop21h 43m

$1,389

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Sun 6/9

1 stop33h 36m

Sydney Kingsford Smith

Sun 6/16

1 stop28h 43m

$1,412

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Sun 9/22

1 stop22h 00m

Sydney Kingsford Smith

Fri 10/4

1 stop29h 10m

$1,435

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Sun 6/9

2 stops30h 42m

Sydney Kingsford Smith

Sun 6/16

1 stop28h 43m

$1,488

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Mon 9/23

1 stop23h 40m

Sydney Kingsford Smith

Sat 10/5

1 stop21h 30m

$1,534

Flights are sorted by cheapest first

Deals found on 5/12

When is the best time to 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 May 10, 2024.
The best time to book flights from St. Louis to Sydney is 60 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.
Search Deals

When is the cheapest time to fly from St. Louis to Sydney?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Sydney. Price data was last updated on May 5, 2024.
Morning
Noon
Afternoon
Evening
All times are departure.
Travelers seeking maximum savings on their St. Louis to Sydney flight should consider departing on Monday mornings when fares are most often at their lowest. Wednesday mornings flights should be avoided if possible as fares are typically the most expensive at this time.
Search Deals

Average price of flights to Sydney by month

Plan your trip from St. Louis to Sydney by taking into account the cheapest months to travel. The average price of a one-way flight from St. Louis to Sydney is currently $0 while a round-trip flight costs $1,321. Price data was last updated on May 5, 2024.

Currently, February is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,110). Flying from St. Louis to Sydney in July is currently the most expensive (average of $1,427). 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.

January

$1,298

February

$1,110

March

$1,132

April

$1,359

May

$1,369

June

$1,386

July

$1,427

August

$1,305

September

$1,276

October

$1,214

November

$1,279

December

$1,397

Temperature and rainfall in Sydney by month

Plan your trip to Sydney by taking into account the average temperature and rainfall totals by month.

SYD

Temperature

51.8 - 71.6 °F

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 May 12, 2024.
Get a feel of what it's like to fly with Air Canada, United Airlines and Qantas Airways from St. Louis to Sydney by reading reviews from past customers. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
7.8
Good
1,089 reviews

Food

7.5

Entertainment

8.0

Overall

7.8

Boarding

8.0

Crew

8.2

Comfort

7.8

Reviews

1 / 10

Flight took off a hour late due to electrical problems. The space between the seats felt like the tightest ever. When the person in front reclines their seat, they are in your lap and you cant even get up to go to the bathroom. I had to ask everyone in my aisle to get up and exit and I had to climb over the seats to exit. The stewards almost never came by to pick up trash. We were told the alcohol would be served after the meal but they never came back through and offered it. Most international flights offer a warm cloth in the morning, not this flight. No interactions with staff except during meal service, otherwise they were nowhere to be found. When they were around, they were very nice, but service was definitely lacking.

7.8
Good
1,089 reviews
7.8
Good
1,089 reviews

Food

7.5

Entertainment

8.0

Overall

7.8

Boarding

8.0

Crew

8.2

Comfort

7.8

Reviews

1 / 10

Flight took off a hour late due to electrical problems. The space between the seats felt like the tightest ever. When the person in front reclines their seat, they are in your lap and you cant even get up to go to the bathroom. I had to ask everyone in my aisle to get up and exit and I had to climb over the seats to exit. The stewards almost never came by to pick up trash. We were told the alcohol would be served after the meal but they never came back through and offered it. Most international flights offer a warm cloth in the morning, not this flight. No interactions with staff except during meal service, otherwise they were nowhere to be found. When they were around, they were very nice, but service was definitely lacking.

7.7
Good
973 reviews
7.8
Good
1,089 reviews

Food

7.5

Entertainment

8.0

Overall

7.8

Boarding

8.0

Crew

8.2

Comfort

7.8

Reviews

1 / 10

Flight took off a hour late due to electrical problems. The space between the seats felt like the tightest ever. When the person in front reclines their seat, they are in your lap and you cant even get up to go to the bathroom. I had to ask everyone in my aisle to get up and exit and I had to climb over the seats to exit. The stewards almost never came by to pick up trash. We were told the alcohol would be served after the meal but they never came back through and offered it. Most international flights offer a warm cloth in the morning, not this flight. No interactions with staff except during meal service, otherwise they were nowhere to be found. When they were around, they were very nice, but service was definitely lacking.

7.4
Good
10,981 reviews
7.8
Good
1,089 reviews

Food

7.5

Entertainment

8.0

Overall

7.8

Boarding

8.0

Crew

8.2

Comfort

7.8

Reviews

1 / 10

Flight took off a hour late due to electrical problems. The space between the seats felt like the tightest ever. When the person in front reclines their seat, they are in your lap and you cant even get up to go to the bathroom. I had to ask everyone in my aisle to get up and exit and I had to climb over the seats to exit. The stewards almost never came by to pick up trash. We were told the alcohol would be served after the meal but they never came back through and offered it. Most international flights offer a warm cloth in the morning, not this flight. No interactions with staff except during meal service, otherwise they were nowhere to be found. When they were around, they were very nice, but service was definitely lacking.

7.3
Good
14,608 reviews
7.8
Good
1,089 reviews

Food

7.5

Entertainment

8.0

Overall

7.8

Boarding

8.0

Crew

8.2

Comfort

7.8

Reviews

1 / 10

Flight took off a hour late due to electrical problems. The space between the seats felt like the tightest ever. When the person in front reclines their seat, they are in your lap and you cant even get up to go to the bathroom. I had to ask everyone in my aisle to get up and exit and I had to climb over the seats to exit. The stewards almost never came by to pick up trash. We were told the alcohol would be served after the meal but they never came back through and offered it. Most international flights offer a warm cloth in the morning, not this flight. No interactions with staff except during meal service, otherwise they were nowhere to be found. When they were around, they were very nice, but service was definitely lacking.

7.0
Good
6,934 reviews
7.8
Good
1,089 reviews

Food

7.5

Entertainment

8.0

Overall

7.8

Boarding

8.0

Crew

8.2

Comfort

7.8

Reviews

1 / 10

Flight took off a hour late due to electrical problems. The space between the seats felt like the tightest ever. When the person in front reclines their seat, they are in your lap and you cant even get up to go to the bathroom. I had to ask everyone in my aisle to get up and exit and I had to climb over the seats to exit. The stewards almost never came by to pick up trash. We were told the alcohol would be served after the meal but they never came back through and offered it. Most international flights offer a warm cloth in the morning, not this flight. No interactions with staff except during meal service, otherwise they were nowhere to be found. When they were around, they were very nice, but service was definitely lacking.

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.
  • Can I find flights from St. Louis to Sydney for under $1,200 on Cheapflights?

    Yes, there are multiple flights from St. Louis to Sydney for under $1,200. The cheapest flight booked recently is on Air Canada for just $1,145, but on average you can expect to pay $1,360.

  • What are the cheapest airlines flying from St. Louis to Sydney round-trip?

    According to our current data, Air Canada ($1,145), United Airlines ($1,389), and Qantas Airways ($1,412) offers the cheapest pricing from St. Louis to Sydney. Air Canada is priced at 32% lower than the current average price of a flight leaving 3 months from now.

  • What are the most popular airlines that fly from St. Louis to Sydney?

  • What does STL to SYD mean?

    These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Lambert-St Louis Airport to Sydney Kingsford Smith Airport flight would often be abbreviated as a STL to SYD flight.

  • Can I find deals for flights from St. Louis to Sydney that include extra baggage allowance?

    The amount of baggage you can bring on your St. Louis to Sydney flight depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.

  • Can I find deals on flights from St. Louis to Sydney with specific airlines?

    Yes, Cheapflights allows you to browse and filter St. Louis to Sydney flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.

  • 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.

  • Can I find deals for flights from St. Louis to Sydney that allow pets onboard?

    Many airlines flying from St. Louis to Sydney offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.

  • Can I find deals on last-minute flights from St. Louis to Sydney?

    Yes, you can often find last-minute deals on St. Louis to Sydney flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.

  • How recently were the St. Louis to Sydney flight deals updated?

    The St. Louis to Sydney flight deals you see on this page were last updated on 5/12.

See more FAQs

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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.

Top 6 airlines flying from St. Louis to Sydney

Discover the top 6 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 2,633,403 searches. Data last updated May 12, 2024.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$983Average$1,364FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
DeltaCheapest$1,013Average$1,535FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
Air CanadaCheapest$1,176Average$1,319FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
American AirlinesCheapest$1,214Average$1,550FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
Qantas AirwaysCheapest$1,257Average$1,780FlexibilityNo cancel feeOn-time74%
Search Qantas Airways flights
Air New ZealandCheapest$1,422Average$1,597FlexibilityNo cancel feeOn-time78%
Search Air New Zealand flights

Search flights from St. Louis to Sydney by cabin class

Find flights from St. Louis to Sydney, based on your preferred cabin class, be it economy, premium economy, business, or first class.

Fly with Cheapflights

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Users can book flights with no change fees policies with our dedicated filters. Book flights from St. Louis to Sydney flexibly with Cheapflights today.

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