Detroit (DTW) to Sydney (SYD): 9,468 miles (15,237 km) great-circle, about 19h 25m nonstop by our estimate. Cheapest fare observed: $1184 round-trip on Frontier, with 3 stops, departing May 8, 2026.
$1184 round-trip, Frontier F91957, departing 2026-05-08 at 08:52, returning 2026-05-15. The recorded itinerary left on a Friday, returning on a Friday 7 nights later; the fare was observed 13 days before departure. "Book this flight" opens Kiwi.com with the same airline and dates.
At $1184, it ranked 27th of the 30 round-trip fares we recorded from DTW (median $275). That is 12.5 cents per great-circle mile (round-trip price over one-way distance), below the DTW median of 22.2 cents across 30 round-trip routes.
Routes from DTW of similar length: Dhaka (7,855 mi) at $1390 and Baghdad (6,255 mi) at $1557.
Frontier had the cheapest fare on 17 of 30 DTW routes. It is the longest of the 30 routes we track from DTW.
Of 8 departure airports with a fare to Sydney, Detroit (DTW) ranked 7th at $1184. Lowest: $122 from Melbourne (MEL); highest: $1827 from Charlotte (CLT); 5 nonstop. Cheapest-fare airlines (routes): Jetstar (4), Frontier (2), Air India Express (1) and Qantas (1).
That depends on your passport and trip, so check the official source for Australia: Australian Department of Home Affairs: visa finder. Connecting elsewhere? Check that country's transit rules too.
Travelpayouts fares (cheapest per route, observed April 25, 2026); OurAirports coordinates and elevations; IANA zones America/New_York, Australia/Sydney; flight time is our estimate.