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Cheap flights from St. Louis (STL) to Sydney (SYD) from $918

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 8/14. 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
Jun 4 — Jun 111
From?
To?
Tue 6/4
Tue 6/11
1 adult, Economy
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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 Monday and return on a Wednesday

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 30, 2024.

Popular in

December

Cheapest in

February

Round-trip from

$1,097

One-way from

$918
High demand for flights, 36% potential price rise
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Best time to find cheap flights, 20% potential price drop
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From Lambert-St Louis to Sydney Kingsford Smith
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One-way flight from Lambert-St Louis to Sydney Kingsford Smith
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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 $1,195.

What is the cheapest time of day to fly from STL to SYD?

It’s optimal to fly from St. Louis to Sydney in the morning. By choosing this option you can save up to 6% on the cost of your flight, compared to a flight in the evening.

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 2,784,634 searches. Data last updated May 30, 2024.
Peruse some of the lowest-priced United Airlines flights we've found from St. Louis to Sydney. It's recommended that users confirm their flight details before booking.
Wed 8/149:08 amSTL - SYD
2 stops30h 47mUnited Airlines
Tue 9/310:20 amSYD - STL
1 stop21h 43mUnited Airlines
Deal found 5/29$1,330
Sat 7/64:36 pmSTL - SYD
2 stops47h 24mUnited Airlines
Sat 7/2710:20 amSYD - STL
2 stops24h 17mUnited Airlines
Deal found 5/29$1,396
Fri 8/166:08 amSTL - SYD
2 stops33h 52mUnited Airlines
Fri 8/2310:20 amSYD - STL
1 stop29h 07mUnited Airlines
Deal found 5/29$1,425
Thu 6/276:30 amSTL - SYD
2 stops33h 30mUnited Airlines
Thu 7/410:20 amSYD - STL
2 stops39h 05mUnited Airlines
Deal found 5/28$1,430

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 2,784,634 searches. Data last updated May 30, 2024.
Browse through some of the cheapest Air Canada flights traveling from St. Louis to Sydney. Check back soon if you're not seeing flights that suit your needs.
Wed 8/1412:00 pmSTL - SYD
3 stops52h 20mAir Canada
Tue 9/39:20 amSYD - STL
2 stops45h 00mAir Canada
Deal found 5/29$1,423
Fri 8/1612:00 pmSTL - SYD
3 stops52h 20mAir Canada
Fri 8/239:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/29$1,465
Fri 8/2312:00 pmSTL - SYD
2 stops28h 20mAir Canada
Wed 8/289:20 amSYD - STL
2 stops50h 45mAir Canada
Deal found 5/30$1,539
Fri 8/2312:00 pmSTL - SYD
3 stops52h 20mAir Canada
Wed 8/289:20 amSYD - STL
2 stops50h 45mAir Canada
Deal found 5/30$1,545
Sat 7/611:30 amSTL - SYD
2 stops52h 50mAir Canada
Sat 7/279:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/29$1,583
Sat 7/611:30 amSTL - SYD
3 stops52h 50mAir Canada
Sat 7/279:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/29$1,588
Thu 6/2711:00 amSTL - SYD
2 stops29h 20mAir Canada
Thu 7/49:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/28$1,746
Fri 7/511:30 amSTL - SYD
3 stops52h 50mAir Canada
Fri 7/129:20 amSYD - STL
2 stops26h 45mAir Canada
Deal found 5/29$1,933
Mon 8/1212:00 pmSTL - SYD
3 stops52h 20mAir Canada
Sat 8/179:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/29$2,040

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 2,784,634 searches. Prices were last updated on May 30, 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.
Thu 6/276:29 amSTL - SYD
1 stop34h 41mQantas Airways
Thu 7/45:35 pmSYD - STL
1 stop20h 23mQantas Airways
Deal found 5/28$1,426
Thu 6/276:30 amSTL - SYD
2 stops33h 30mUnited Airlines
Thu 7/410:20 amSYD - STL
2 stops39h 05mUnited Airlines
Deal found 5/28$1,430
Fri 6/216:06 amSTL - SYD
2 stops33h 29mDelta
Sat 7/139:25 amSYD - STL
2 stops29h 14mDelta
Deal found 5/29$1,512
Thu 6/276:29 amSTL - SYD
1 stop33h 36mAmerican Airlines
Thu 7/49:15 amSYD - STL
2 stops39h 33mAmerican Airlines
Deal found 5/28$1,582
Thu 6/2711:00 amSTL - SYD
2 stops29h 20mAir Canada
Thu 7/49:20 amSYD - STL
3 stops50h 45mAir Canada
Deal found 5/28$1,746
Fri 6/214:55 pmSTL - SYD
2 stops24h 50mAir New Zealand
Sat 7/1311:50 amSYD - STL
2 stops25h 27mAir New Zealand
Deal found 5/30$2,120
Sun 6/24:55 pmSTL - SYD
2 stops24h 50mAir New Zealand
Tue 6/411:50 amSYD - STL
2 stops23h 35mAir New Zealand
Deal found 5/29$2,172
Sun 6/26:15 amSTL - SYD
2 stops35h 30mAir New Zealand
Tue 6/411:50 amSYD - STL
2 stops25h 25mAir New Zealand
Deal found 5/29$2,183
Fri 6/214:55 pmSTL - SYD
2 stops24h 50mMultiple Airlines
Sat 7/138:45 amSYD - STL
3 stops28h 35mMultiple Airlines
Deal found 5/30$2,241

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 2,784,634 searches. Data last updated May 30, 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.
Wed 8/149:08 amSTL - SYD
2 stops30h 47mUnited Airlines
Tue 9/310:20 amSYD - STL
1 stop21h 43mUnited Airlines
Deal found 5/29$1,330
Sat 7/64:36 pmSTL - SYD
2 stops47h 24mUnited Airlines
Sat 7/2710:20 amSYD - STL
2 stops24h 17mUnited Airlines
Deal found 5/29$1,396
Wed 8/1412:00 pmSTL - SYD
3 stops52h 20mAir Canada
Tue 9/39:20 amSYD - STL
2 stops45h 00mAir Canada
Deal found 5/29$1,423
Fri 8/166:08 amSTL - SYD
2 stops33h 52mUnited Airlines
Fri 8/2310:20 amSYD - STL
1 stop29h 07mUnited Airlines
Deal found 5/29$1,425
Thu 6/276:29 amSTL - SYD
1 stop34h 41mQantas Airways
Thu 7/45:35 pmSYD - STL
1 stop20h 23mQantas Airways
Deal found 5/28$1,426
Thu 6/276:30 amSTL - SYD
2 stops33h 30mUnited Airlines
Thu 7/410:20 amSYD - STL
2 stops39h 05mUnited Airlines
Deal found 5/28$1,430
Mon 8/122:35 pmSTL - SYD
2 stops25h 00mDelta
Sat 8/179:25 amSYD - STL
2 stops27h 03mDelta
Deal found 5/29$1,462
Fri 8/1612:00 pmSTL - SYD
3 stops52h 20mAir Canada
Fri 8/239:20 amSYD - STL
2 stops45h 01mAir Canada
Deal found 5/29$1,465
Sat 9/1410:10 amSTL - SYD
2 stops30h 10mAir Canada
Sat 9/219:20 amSYD - STL
2 stops45h 00mAir Canada
Deal found 5/29$1,498

One-way flights to Sydney from St. Louis

Search for one-way flight options from St. Louis to Sydney. Find affordable one-way fares based on user searches. Compare prices and availability to plan your one-way journey according to your preferred dates and budget. Over the last 7 days, Cheapflights users made 2,784,634 searches. Data last updated May 30, 2024.
Users traveling one-way from St. Louis to Sydney can select one of these great deals. Users needing a return flight from St. Louis to Sydney should utilize the search form above.
Wed 8/1411:36 amSTL - SYD
3 stops33h 09mMultiple Airlines
Deal found 5/28$918
Wed 8/1411:10 amSTL - SYD
2 stops32h 25mAir New Zealand
Deal found 5/28$1,094
Wed 8/144:18 pmSTL - SYD
1 stop22h 57mQantas Airways
Deal found 5/28$1,215

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 2,784,634 searches. Data last updated May 30, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$1,330 - $1,861

Route

Depart

Return

Price

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Wed 8/14

2 stops30h 47m

Sydney Kingsford Smith

Tue 9/3

1 stop21h 43m

$1,330

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Sat 7/6

2 stops47h 24m

Sydney Kingsford Smith

Sat 7/27

2 stops24h 17m

$1,396

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Wed 8/14

3 stops52h 20m

Sydney Kingsford Smith

Tue 9/3

2 stops45h 00m

$1,423

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Thu 6/27

1 stop34h 41m

Sydney Kingsford Smith

Thu 7/4

1 stop20h 23m

$1,426

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Mon 8/12

2 stops25h 00m

Sydney Kingsford Smith

Sat 8/17

2 stops27h 03m

$1,462

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Fri 8/16

3 stops52h 20m

Sydney Kingsford Smith

Fri 8/23

2 stops45h 01m

$1,465

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Wed 8/14

3 stops33h 09m

Sydney Kingsford Smith

Tue 9/3

3 stops35h 36m

$1,565

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Thu 6/27

1 stop33h 36m

Sydney Kingsford Smith

Thu 7/4

2 stops39h 33m

$1,582

Lambert-St LouisSydney Kingsford Smith

STL - SYD

STLSYD

Lambert-St Louis

Mon 7/8

2 stops24h 42m

Sydney Kingsford Smith

Sun 7/14

2 stops43h 07m

$1,861

Flights are sorted by cheapest first

Deals found on 5/29

How far ahead should I 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 24, 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

What is the cheapest day 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 26, 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

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 round-trip 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.

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 30, 2024.
Get a feel of what it's like to fly with United Airlines, Air Canada 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.
Air New Zealand
8.3
Very good
610 reviews
Check prices

Crew

8.7

Food

7.6

Entertainment

7.9

Overall

8.3

Comfort

8.1

Boarding

8.4

Reviews

1 / 10

Terrible. Boarding pass priority boarding. Got no service, no food which looked yucky, why seat people in first class then treat them low class?

Air New Zealand
8.3
Very good
610 reviews
Air New Zealand
8.3
Very good
610 reviews
Check prices

Crew

8.7

Food

7.6

Entertainment

7.9

Overall

8.3

Comfort

8.1

Boarding

8.4

Reviews

1 / 10

Terrible. Boarding pass priority boarding. Got no service, no food which looked yucky, why seat people in first class then treat them low class?

Delta
8.0
Very good
10,457 reviews
Air New Zealand
8.3
Very good
610 reviews
Check prices

Crew

8.7

Food

7.6

Entertainment

7.9

Overall

8.3

Comfort

8.1

Boarding

8.4

Reviews

1 / 10

Terrible. Boarding pass priority boarding. Got no service, no food which looked yucky, why seat people in first class then treat them low class?

Qantas Airways
7.6
Good
942 reviews
Air New Zealand
8.3
Very good
610 reviews
Check prices

Crew

8.7

Food

7.6

Entertainment

7.9

Overall

8.3

Comfort

8.1

Boarding

8.4

Reviews

1 / 10

Terrible. Boarding pass priority boarding. Got no service, no food which looked yucky, why seat people in first class then treat them low class?

United Airlines
7.4
Good
10,777 reviews
Air New Zealand
8.3
Very good
610 reviews
Check prices

Crew

8.7

Food

7.6

Entertainment

7.9

Overall

8.3

Comfort

8.1

Boarding

8.4

Reviews

1 / 10

Terrible. Boarding pass priority boarding. Got no service, no food which looked yucky, why seat people in first class then treat them low class?

American Airlines
7.3
Good
14,284 reviews
Air New Zealand
8.3
Very good
610 reviews
Check prices

Crew

8.7

Food

7.6

Entertainment

7.9

Overall

8.3

Comfort

8.1

Boarding

8.4

Reviews

1 / 10

Terrible. Boarding pass priority boarding. Got no service, no food which looked yucky, why seat people in first class then treat them low class?

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 $1,400 on Cheapflights?

    Yes, there are multiple flights from St. Louis to Sydney for under $1,400. The cheapest flight booked recently is on United Airlines for just $1,330, but on average you can expect to pay $1,565.

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

    According to our current data, United Airlines ($1,330), Air Canada ($1,423), and Qantas Airways ($1,426) offers the cheapest pricing from St. Louis to Sydney. United Airlines is priced at 20% lower than the current average price of a flight leaving 3 months from now.

  • 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 5/29.

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

    Consider American Airlines, Air Canada or Delta when booking your flight. These represent the most popular airlines when flying from St. Louis to Sydney.

  • What is the cheapest month to book a flight from St. Louis to Sydney?

    Currently, February is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,097). Flying from St. Louis to Sydney in July is currently the most expensive (average of $1,385). 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

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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
Columbia to Sydney flights
Springfield to Coolangatta flights

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 2,784,634 searches. Data last updated May 30, 2024.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$986Average$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$1,205Average$1,523FlexibilityNo 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
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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.
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Can Cheapflights find flights from St. Louis to Sydney with no change fees?

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

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

Not ready to book yet? You can track prices for flights from St. Louis to Sydney on Cheapflights with our Price Alert feature and get notified when better prices are available.

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