The new aircraft flew the Seattle skies in preparation for its handover to Air New Zealand, expected in July.
Air New Zealand is the launch customer for the Boeing 787-9. Ten of the stretch versions of the original Boeing 787-8 are on order.
The planes were first expected to be ready for the airline in late 2010, but the 787 programme has been plagued by delays.
Boeing has said the 787-9 will offer more space, light, go further and offer greater fuel efficiency.
Air New Zealand has previously said the new plane would first be launched on the Auckland to Perth route from October 15, after pilot training.
Routes to Tokyo and Shanghai from Auckland are expected to launch near the end of the year.
This first test flight, known as a B1 flight, included the two pilots who put the aircraft through its paces to verify performance. Functionality of the cabin was also assessed during the flight.
The aircraft, in its black with silver fern and koru livery, departed from Paine Field airport north of Seattle at 1.45pm local time.
The 787-9 reached an altitude of 11,800 metres and returned to the same airport 3 hours and 10 minutes later.