$666+ Cheap flights from St. Louis (STL) to Sydney (SYD)
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 10/14. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SYD
Oct 10 — Oct 171
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Sydney with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from St. Louis to Sydney
Cheapest
Best
Last-minute
One-way
Cheapest flights from St. Louis to SydneyExplore 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 September 10, 2026.
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 September 10, 2026.
This FlightHub deal was found by Cheapflights users on 9/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/911:00 am -
2 stops28h 35m
Tue 11/247:25 pm -
2 stops43h 50m
Deal found 9/8![Air New Zealand logo]()
$1,257
This FlightHub deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/187:08 am -
2 stops46h 42m
Sun 11/89:55 am -
2 stops29h 31m
Deal found 9/7![Air New Zealand logo]()
$1,305
This oojo deal was found by Cheapflights users on 9/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2112:47 pm -
1 stop26h 08m
Wed 10/281:05 pm -
1 stop19h 58m
Deal found 9/6![Qantas Airways logo]()
$1,327
This United Airlines deal was found by Cheapflights users on 9/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/211:29 pm -
2 stops26h 26m
Wed 10/289:15 am -
1 stop20h 58m
Deal found 9/6![United Airlines logo]()
$1,330
This United Airlines deal was found by Cheapflights users on 9/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/911:00 am -
1 stop27h 00m
Tue 11/2411:20 am -
2 stops23h 45m
Deal found 9/8![United Airlines logo]()
$1,331
This Justfly.com deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/173:12 pm -
2 stops25h 33m
Sun 10/2511:50 am -
2 stops26h 36m
Deal found 9/7![Air New Zealand logo]()
$1,333
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/133:12 pm -
2 stops24h 43m
Wed 11/189:15 am -
1 stop24h 35m
Deal found 9/7![United Airlines logo]()
$1,335
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/184:39 pm -
2 stops23h 21m
Sun 11/811:50 am -
1 stop23h 15m
Deal found 9/7![United Airlines logo]()
$1,380
This United Airlines deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/258:30 am -
1 stop30h 30m
Sun 11/19:15 am -
1 stop21h 58m
Deal found 9/9![United Airlines logo]()
$1,381
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/133:12 pm -
2 stops24h 43m
Fri 11/1311:20 am -
2 stops26h 39m
Deal found 9/7![United Airlines logo]()
$1,385
This Orbitz deal was found by Cheapflights users on 9/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/910:53 am -
3 stops29h 42m
Tue 11/2411:20 am -
3 stops38h 35m
Deal found 9/8![Air Canada logo]()
$1,390
Best flights from St. Louis to SydneyDiscover carefully curated flight deals from St. Louis to Sydney that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 10, 2026.
Discover carefully curated flight deals from St. Louis to Sydney that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 10, 2026.
This United Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/12:50 pm -
2 stops25h 15m
Wed 12/99:15 am -
1 stop21h 51m
Deal found 9/5![United Airlines logo]()
$1,330
This Air New Zealand deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air New Zealand is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/38:05 am -
3 stops31h 30m
Wed 2/242:05 pm -
3 stops26h 14m
Deal found 9/7![Multiple Airlines logo]()
$1,342
This Delta deal was found by Cheapflights users on 9/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/233:52 pm -
2 stops23h 58m
Wed 10/710:15 am -
2 stops24h 00m
Deal found 9/10![Delta logo]()
$1,515
This United Airlines deal was found by Cheapflights users on 9/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/911:00 am -
1 stop27h 00m
Tue 11/2411:20 am -
2 stops23h 45m
Deal found 9/8![United Airlines logo]()
$1,331
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/56:15 am -
2 stops33h 40m
Mon 10/1210:30 am -
2 stops24h 13m
Deal found 9/7![United Airlines logo]()
$1,335
This United Airlines deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/253:15 pm -
2 stops24h 50m
Sun 11/19:15 am -
1 stop21h 58m
Deal found 9/9![United Airlines logo]()
$1,381
This United Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/136:15 am -
2 stops33h 40m
Fri 11/1311:20 am -
2 stops22h 37m
Deal found 9/5![United Airlines logo]()
$1,385
This United Airlines deal was found by Cheapflights users on 9/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/61:29 pm -
2 stops26h 26m
Tue 10/1311:20 am -
2 stops21h 17m
Deal found 9/6![United Airlines logo]()
$1,482
Last-minute flights from St. Louis to SydneyDiscover last-minute flight deals from St. Louis to Sydney. Data last updated September 10, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Sydney. Data last updated September 10, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/133:12 pm -
2 stops24h 43m
Wed 11/189:15 am -
1 stop24h 35m
Deal found 9/7![United Airlines logo]()
$1,335
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/133:12 pm -
2 stops24h 43m
Fri 11/1311:20 am -
2 stops26h 39m
Deal found 9/7![United Airlines logo]()
$1,385
This Justfly.com deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/173:12 pm -
2 stops25h 33m
Sun 10/2511:50 am -
2 stops26h 36m
Deal found 9/7![Air New Zealand logo]()
$1,333
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/173:12 pm -
2 stops24h 43m
Sun 10/2511:50 am -
1 stop22h 15m
Deal found 9/7![United Airlines logo]()
$1,430
This FlightHub deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/187:08 am -
2 stops46h 42m
Sun 11/89:55 am -
2 stops29h 31m
Deal found 9/7![Air New Zealand logo]()
$1,305
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/184:39 pm -
2 stops23h 21m
Sun 11/811:50 am -
1 stop23h 15m
Deal found 9/7![United Airlines logo]()
$1,380
This American Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/186:04 am -
1 stop33h 26m
Sun 11/82:05 pm -
1 stop21h 11m
Deal found 9/7![American Airlines logo]()
$1,407
This oojo deal was found by Cheapflights users on 9/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2112:47 pm -
1 stop26h 08m
Wed 10/281:05 pm -
1 stop19h 58m
Deal found 9/6![Qantas Airways logo]()
$1,327
This United Airlines deal was found by Cheapflights users on 9/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/211:29 pm -
2 stops26h 26m
Wed 10/289:15 am -
1 stop20h 58m
Deal found 9/7![United Airlines logo]()
$1,330
This United Airlines deal was found by Cheapflights users on 9/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/258:30 am -
1 stop30h 30m
Sun 11/19:15 am -
1 stop21h 58m
Deal found 9/9![United Airlines logo]()
$1,381
One-way flights from St. Louis to SydneySearch for one-way flight options from St. Louis to Sydney. Find affordable one-way fares based on user searches. Data last updated September 10, 2026.
Search for one-way flight options from St. Louis to Sydney. Find affordable one-way fares based on user searches. Data last updated September 10, 2026.
This Kiwi.com deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/144:19 pm -
2 stops47h 11m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![Multiple Airlines logo]()
$666
This United Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/136:15 am -
2 stops33h 40m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![United Airlines logo]()
$708
This Kiwi.com deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/168:00 pm -
3 stops58h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![Multiple Airlines logo]()
$739
This Kiwi.com deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/128:00 pm -
3 stops58h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![Multiple Airlines logo]()
$748
This Kiwi.com deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/157:02 am -
2 stops32h 28m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![Multiple Airlines logo]()
$778
This United Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/157:08 am -
1 stop32h 47m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![United Airlines logo]()
$787
This United Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/165:36 pm -
2 stops46h 19m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![United Airlines logo]()
$793
This United Airlines deal was found by Cheapflights users on 9/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/68:35 am -
2 stops31h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/6![United Airlines logo]()
$798
This Qantas Airways deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Qantas Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/166:04 am -
1 stop34h 01m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![Qantas Airways logo]()
$822
This United Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/105:36 pm -
2 stops46h 19m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/5![United Airlines logo]()
$824
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 September 10, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $1,257 (FlightHub) |
One-way from | $666 (Kiwi.com) |
Popular in | December |
Cheapest in | July |
Average price | $1,398 |
Cheapflights 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, Cheapflights users made 7,457,451 searches. Data last updated September 10, 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
Cheapest round-trip
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Tue 10/13
11:10 am-7:55 am
2 stops28h 45m
Sydney Kingsford Smith
Wed 12/31
12:00 am-8:00 am
Nonstop0h 00m
$708
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Fri 10/16
5:36 pm-7:55 am
2 stops46h 19m
Sydney Kingsford Smith
Wed 12/31
12:00 am-8:00 am
Nonstop0h 00m
$793
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Tue 10/6
8:35 am-7:55 am
2 stops31h 20m
Sydney Kingsford Smith
Wed 12/31
12:00 am-8:00 am
Nonstop0h 00m
$798
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Fri 10/16
6:04 am-8:05 am
1 stop34h 01m
Sydney Kingsford Smith
Wed 12/31
12:00 am-8:00 am
Nonstop0h 00m
$822
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Sat 10/10
5:36 pm-7:55 am
2 stops46h 19m
Sydney Kingsford Smith
Wed 12/31
12:00 am-8:00 am
Nonstop0h 00m
$824
Quickest round-trip
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Sun 10/11
1:29 pm-7:55 am
2 stops26h 26m
Sydney Kingsford Smith
Wed 12/31
12:00 am-8:00 am
Nonstop0h 00m
$888
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Tue 12/1
2:50 pm-9:05 am
2 stops25h 15m
Sydney Kingsford Smith
Wed 12/9
9:15 am-2:06 pm
1 stop21h 51m
$1,330
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Mon 11/9
11:00 am-7:00 am
1 stop27h 00m
Sydney Kingsford Smith
Tue 11/24
11:20 am-6:05 pm
2 stops23h 45m
$1,331
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Mon 10/5
6:15 am-7:55 am
2 stops33h 40m
Sydney Kingsford Smith
Mon 10/12
10:30 am-6:43 pm
2 stops24h 13m
$1,335
St. LouisSydney
STL Lambert-St Louis - SYD Sydney Kingsford Smith
STLSYD
Lambert-St Louis
Wed 2/3
8:05 am-8:35 am
3 stops31h 30m
Sydney Kingsford Smith
Wed 2/24
2:05 pm-11:19 pm
3 stops26h 14m
$1,342
Showing 1-10 of 15 resultsSorted by cheapest first
Compare providers for flights from St. Louis to Sydney
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Sydney in September.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on St. Louis-Sydney flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Sydney flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Sydney flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on St. Louis-Sydney flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Sydney flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
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.
STL-SYD
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.
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, July is the cheapest month in which you can book a flight from St. Louis to Sydney (average of $1,161). Flying from St. Louis to Sydney in December is currently the most expensive (average of $1,634). 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 to fly round-trip from St. Louis to Sydney?
Airfare is below average for this route at the moment.
St. Louis to Sydney flights typically cost between $1,372 and $1,590 in February.The cheapest round-trip price found within the last 5 days was $1,257 on Air New Zealand (Feb 8-Feb 15).
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 September 10, 2026.
Get a feel of what it's like to fly with Qantas Airways,United Airlines, andAmerican Airlines from St. Louis to Sydney by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Overall
7.5
Boarding
7.7
Entertainment
7.2
Crew
8.1
Food
7.0
Comfort
7.4
Reviews
1 / 20
4.0
OkayRobyn,Aug 2026
LAX - SYD
Overall
7.5
Boarding
7.7
Entertainment
7.2
Crew
8.1
Food
7.0
Comfort
7.4
Reviews
1 / 20
4.0
OkayRobyn,Aug 2026
LAX - SYD
Overall
7.5
Boarding
7.7
Entertainment
7.2
Crew
8.1
Food
7.0
Comfort
7.4
Reviews
1 / 20
4.0
OkayRobyn,Aug 2026
LAX - SYD
Overall
7.5
Boarding
7.7
Entertainment
7.2
Crew
8.1
Food
7.0
Comfort
7.4
Reviews
1 / 20
4.0
OkayRobyn,Aug 2026
LAX - SYD
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Top 3 airlines flying from St. Louis to Sydney
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| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$1,094 | Average$1,372 | FlexibilityNo cancel fee | On-time74% | |
| Cheapest$1,144 | Average$1,381 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$1,233 | Average$1,549 | FlexibilityNo cancel fee | On-time71% |