Cheap flights from Seattle to Sydney from $639
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to Sydney departing on 18/8. 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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How to get the cheapest flight ticket from Seattle 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 March is, on average, the cheapest month to fly to Sydney from Seattle, with most prices found around $1,608. If you aren’t able to travel to Sydney during the month of March, then flying in February is also cheap. Prices for this month can be found on momondo for an average of $1,636.
What is the cheapest day to depart on your flight to Sydney?
Our data shows that Monday is the least expensive day to fly to Sydney. Tickets to fly out on this day can be as low as $1,509. The most expensive day to fly to Sydney is Saturday, with ticket prices averaging around $1,824.
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 at midday. momondo users have found flights departing from Seattle to Sydney at midday for as low as $0. 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 $1,769 on average. Flights to Sydney from Seattle 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 Seattle when booking 24 weeks ahead of your departure date. In general, you can expect to find flights to Sydney for around $1,786 when searching 24 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Sydney from Seattle for as low as $1,602 on momondo.
When to book flights from Seattle to Sydney
Cheap Seattle to Sydney (SEA to SYD) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Seattle to Sydney
How far is Seattle/Tacoma Intl to Sydney Kingsford Smith by plane?
Seattle/Tacoma Intl and Sydney Kingsford Smith are 12462.2 km apart from one another. In terms of flight time, this usually takes a little over 18h 20m.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport?
Prices for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport refresh daily.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport?
The number of operators available for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport is 2 as of April 2025.
How old do you have to be to fly from Seattle/Tacoma 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 Seattle/Tacoma Intl 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.
What is the most popular airline from Seattle to Sydney?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Seattle to Sydney is Air Canada (71% of total bookings). The next most popular airline is United Airlines (29%).
Best airlines flying from Seattle to Sydney
Compare and see reviews for airlines that fly from Seattle to Sydney with momondo
| Airline | Rating | Free cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $1,177 | Free cancellation | Rating 7.4 8,696 reviews | |||
| PriceFrom $1,312 | Free cancellation | Rating 7.0 9,228 reviews |
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Why should I use momondo to find a flight deal from Seattle to Sydney?
We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Seattle to Sydney for you.
Can I find flights from Seattle to Sydney with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for Seattle to Sydney flights to just show those with flexible booking policies.
How can momondo help me find flights from Seattle to Sydney?
Once you have performed a search for Seattle 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 Seattle to Sydney right now. Can momondo alert me if prices change?
Of course. momondo tracks the price of Seattle to Sydney flights. All you need is a valid email address and we will do the rest; it is that quick and easy.