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Cheap flights from Boston to Sydney from $781

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Boston to Sydney departing on 12/4. 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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Cheap return flights

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Delta Logo
17:35 - 08:30
BOS
-
SYD
22h 55m1 stop
Delta Logo
09:40 - 21:22
SYD
-
BOS
26h 42m1 stop
$1,825Delta
Wed, 4 Mar - Mon, 23 Mar
Qantas Airways Logo
08:00 - 09:00
BOS
-
SYD
33h 00m1 stop
Qantas Airways Logo
06:30 - 22:31
SYD
-
BOS
30h 01m2 stops
$1,828Qantas Airways
Wed, 28 Jan - Sat, 4 Jul
American Airlines Logo
08:00 - 09:00
BOS
-
SYD
33h 00m1 stop
American Airlines Logo
14:05 - 19:35
SYD
-
BOS
21h 30m1 stop
$1,830American Airlines
Thu, 5 Feb - Sat, 21 Feb
Delta Logo
18:25 - 06:05
BOS
-
SYD
43h 40m2 stops
Delta Logo
09:40 - 16:14
SYD
-
BOS
21h 34m1 stop
$1,831Delta
Sat, 7 Mar - Wed, 25 Mar
Air Canada Logo
10:15 - 09:35
BOS
-
SYD
31h 20m2 stops
Air Canada Logo
11:20 - 21:37
SYD
-
BOS
26h 17m2 stops
$1,833Air Canada
Thu, 26 Feb - Sun, 8 Mar
American Airlines Logo
09:05 - 08:05
BOS
-
SYD
32h 00m1 stop
American Airlines Logo
09:10 - 18:40
SYD
-
BOS
23h 30m2 stops
$1,836American Airlines
Thu, 2 Apr - Thu, 16 Apr
Air Canada Logo
10:15 - 09:35
BOS
-
SYD
31h 20m3 stops
Air Canada Logo
11:20 - 09:32
SYD
-
BOS
38h 12m2 stops
$1,837Air Canada
Thu, 5 Feb - Sat, 21 Feb
Delta Logo
13:55 - 07:25
BOS
-
SYD
26h 30m1 stop
Delta Logo
09:40 - 21:22
SYD
-
BOS
26h 42m1 stop
$1,839Delta
Wed, 11 Mar - Sat, 28 Mar
Delta Logo
17:00 - 06:35
BOS
-
SYD
23h 35m1 stop
Delta Logo
09:25 - 19:38
SYD
-
BOS
24h 13m1 stop
$1,840Delta
Fri, 15 May - Mon, 24 Aug
Air Canada Logo
05:30 - 09:35
BOS
-
SYD
36h 05m3 stops
Air Canada Logo
11:20 - 21:37
SYD
-
BOS
26h 17m2 stops
$1,842Air Canada
Sat, 28 Feb - Sun, 8 Mar

United Airlines flights from Boston to Sydney

Our best United Airlines deals on Boston to Sydney flight tickets
United Airlines
2 May
BOS20:15Boston Logan Intl
44h 40m
1 stop
SYD06:55Sydney Kingsford Smith
13 May
SYD10:20Sydney Kingsford Smith
27h 34m
2 stops
BOS23:54Boston Logan Intl
$1,843
Find similar
United Airlines
31 Jan
BOS17:57Boston Logan Intl
44h 23m
1 stop
SYD06:20Sydney Kingsford Smith
9 Feb
SYD11:20Sydney Kingsford Smith
23h 37m
2 stops
BOS18:57Boston Logan Intl
$1,851
Find similar
United Airlines
6 Mar
BOS16:59Boston Logan Intl
46h 01m
1 stop
SYD07:00Sydney Kingsford Smith
23 Mar
SYD11:50Sydney Kingsford Smith
21h 38m
1 stop
BOS18:28Boston Logan Intl
$1,854
Find similar

American Airlines flights from Boston to Sydney

Our best American Airlines deals on Boston to Sydney flight tickets
American Airlines
5 Feb
BOS08:00Boston Logan Intl
33h 00m
1 stop
SYD09:00Sydney Kingsford Smith
21 Feb
SYD14:05Sydney Kingsford Smith
21h 30m
1 stop
BOS19:35Boston Logan Intl
$1,830
Find similar
American Airlines
2 Apr
BOS09:05Boston Logan Intl
32h 00m
1 stop
SYD08:05Sydney Kingsford Smith
16 Apr
SYD09:10Sydney Kingsford Smith
23h 30m
2 stops
BOS18:40Boston Logan Intl
$1,836
Find similar
American Airlines
26 Jan
BOS14:43Boston Logan Intl
26h 17m
2 stops
SYD09:00Sydney Kingsford Smith
7 Feb
SYD11:20Sydney Kingsford Smith
25h 12m
2 stops
BOS20:32Boston Logan Intl
$1,881
Find similar

momondo Fare Finder

 
Customise your flight search to find flights from Boston 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 78,305 searches. Data last updated 7 December 2025.
Use the filters below to find and compare flights from Boston to Sydney that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Wed 4/3

17:35-08:30

1 stop22h 55m

Sydney Kingsford Smith

Mon 23/3

09:40-21:22

1 stop26h 42m

$1,825

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Wed 28/1

08:00-09:00

1 stop33h 00m

Sydney Kingsford Smith

Sat 4/7

06:30-22:31

2 stops30h 01m

$1,828

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Thu 5/2

08:00-09:00

1 stop33h 00m

Sydney Kingsford Smith

Sat 21/2

14:05-19:35

1 stop21h 30m

$1,830

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Sat 7/3

18:25-06:05

2 stops43h 40m

Sydney Kingsford Smith

Wed 25/3

09:40-16:14

1 stop21h 34m

$1,831

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Thu 26/2

10:15-09:35

2 stops31h 20m

Sydney Kingsford Smith

Sun 8/3

11:20-21:37

2 stops26h 17m

$1,833

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Thu 2/4

09:05-08:05

1 stop32h 00m

Sydney Kingsford Smith

Thu 16/4

09:10-18:40

2 stops23h 30m

$1,836

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Thu 5/2

10:15-09:35

3 stops31h 20m

Sydney Kingsford Smith

Sat 21/2

11:20-09:32

2 stops38h 12m

$1,837

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Wed 11/3

13:55-07:25

1 stop26h 30m

Sydney Kingsford Smith

Sat 28/3

09:40-21:22

1 stop26h 42m

$1,839

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Fri 15/5

17:00-06:35

1 stop23h 35m

Sydney Kingsford Smith

Mon 24/8

09:25-19:38

1 stop24h 13m

$1,840

BostonSydney

BOS - SYD

BOSSYD

Boston Logan Intl

Sat 28/2

05:30-09:35

3 stops36h 05m

Sydney Kingsford Smith

Sun 8/3

11:20-21:37

2 stops26h 17m

$1,842

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Sydney from

How to get the cheapest flight ticket from Boston 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 cheapest month to fly to Sydney?

The month of September is, on average, the cheapest month to fly to Sydney from Boston, with most prices found around $1,836. If you aren’t able to travel to Sydney during the month of September, then flying in March is also cheap. Prices for this month can be found on momondo for an average of $1,861.

What is the cheapest day to depart on your flight to Sydney?

Our data shows that Tuesday is the least expensive day to fly to Sydney. Tickets to fly out on this day can be as low as $2,029. The most expensive day to fly to Sydney is Friday, with ticket prices averaging around $2,426.

What is the cheapest time of day to depart on your flight to Sydney?

According to our data, the cheapest time of day to fly to Sydney is in the evening. momondo users have found flights departing from Boston to Sydney in the evening for as low as $2,028. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. If you have a flexible travel schedule, then try to avoid flying in the morning when prices are $2,942 on average. Flights to Sydney from Boston in the morning are generally more expensive because this time of day is more convenient for travellers’ schedules.

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

You are more likely to see cheaper flights to Sydney from Boston when booking weeks ahead of your departure date. In general, you can expect to find flights to Sydney for around $2,148 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 Boston for as low as $1,833 on momondo.

Can stopping save me money on Boston to Sydney flights?

You could potentially save up to 27% on your flight if you consider stops on a Boston to Sydney flight.

How have Boston to Sydney flight prices changed over time?

As of December 2025, prices for Boston to Sydney flights are approximately 39% cheaper when compared to flights at the same time last year.

When to book flights from Boston to Sydney

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

Cheap Boston to Sydney (BOS to SYD) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Boston to Sydney

Fastest flight time

27h 50m

Direct flights

None
The fastest flight from Boston to Sydney takes 27h 50m
There are no direct flights from Boston to Sydney. There are no popular flight routes from Boston to Sydney.
Search flight deals

  • How far is Boston Logan Intl to Sydney Kingsford Smith by plane?

    The straight-line distance from Boston Logan Intl to Sydney Kingsford Smith is 16229.2 km. Typically, this will take 22h 50m by plane in normal conditions.

  • When did momondo last update prices for flights from Boston Logan Intl Airport to Sydney Kingsford Smith Airport?

    Prices for flights from Boston Logan Intl Airport to Sydney Kingsford Smith Airport refresh daily.

  • How many operators does momondo search for flights from Boston Logan Intl Airport to Sydney Kingsford Smith Airport?

  • How old do you have to be to fly from Boston Logan Intl 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 Boston Logan Intl 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 required for your trip to Sydney Kingsford Smith Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s licence, and a passport valid for six-months after you plan to arrive at Sydney Kingsford Smith Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

  • What is the most popular airline from Boston to Sydney?

Best airlines flying from Boston to Sydney

Compare and see reviews for airlines that fly from Boston to Sydney with momondo
Airline
Rating
Free cancellation
Price
United AirlinesPriceFrom $1,226Free cancellationRating
7.4
9,076 reviews
Search United Airlines flights
Qantas AirwaysPriceFrom $1,477Free cancellationRating
7.5
948 reviews
Search Qantas Airways flights
American AirlinesPriceFrom $1,491Free cancellationRating
7.2
11,042 reviews
Search American Airlines flights

Travelling to a place near Sydney?

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

Why use momondo?

Why should I use momondo to find a flight deal from Boston to Sydney?

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Sydney from Boston.

Can I find flights from Boston to Sydney with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Sydney from Boston with this policy.

How can momondo help me find flights from Boston to Sydney?

Once you have performed a search for Boston to Sydney flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Boston 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 Boston and alert you when they change.

An easier way to manage your Sydney trip

We make it super easy to schedule, organise and travel with friends or family. Trips is free – and available to use no matter where you book.
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