There’s a huge fare war going on between the US and Australia and New Zealand. These aren’t mistake fares, they’re fares available on a variety of airlines, and they won’t last.

Airfare Spot flags May and August through November fares from Los Angeles and San Francisco to Sydney and Melbourne from $656 roundtrip — non-stop on Qantas, Virgin Australia, and United.

These fares are widely available from $739 regardless of where you book.

To drop the price the additional $80 or more, you need to book via airfare metasearch site Momondo.

And by the way the category of ‘so not worth it’ you can fly China Eastern Los Angeles – Sydney for $604 with connections and even a change of airport.

Via Airfare Spot in May and August you can fly Los Angeles – Auckland roundtrip non-stop from $619. That gives you options of Qantas and United.

With multiple airlines you have a choice of whom to fly and whom to credit the miles to. All things equal I’d choose United. If you’ve got status you can get into economy plus seating making the long haul travel in back more bearable.

Alternatively, credit the miles for United trips to Singapore Airlines KrisFlyer as nearly all United fares earn more miles this way. (United K fares earn one mile per mile flown in Singapore’s KrisFlyer program.)

While a non-elite MileagePlus member crediting United flights to the revenue-based MileagePlus program will only earn 5 miles per dollar on the cost of the ticket excluding taxes, nearly all United fares earn 100% of flown miles when crediting to Singapore Airlines KrisFlyer (.pdf). That means you earn 5-10 times as many miles with Singapore Airlines KrisFlyer for your trip flying United than you would crediting to MileagePlus.

While Singapore miles do expire after 3 years (not 3 years of inactivity), you can top off a KrisFlyer miles account with transfers from American Express, Chase, Citi, and Starwood.

View of the Sydney Opera House from the Park Hyatt Sydney