The suite seats were rolled out last year on Dreamliners and Airbus A321XLR twinjets.
American also retrofitted 20 Boeing 777-300s to have the luxury suite.
The airline said it was the only one to fly from DFW to Auckland and Brisbane, which were two of its longest routes.
It said people could start buying the seats from Monday.
American said it launched a service to Auckland in late 2022, and now had two seasonal routes from Auckland to DFW and Los Angeles (LAX).
“We’re excited to be introducing our new premium Boeing 787-9 aircraft on the popular Auckland-DFW route in early 2026, providing customers with an even more elevated, premium experience than ever before,” said American Airlines’ Jose A. Freig.
Freig, the airline’s vice-president for international and in-flight dining operations, said long-distance flyers wanted more comfort and functionality.
The airline said its premium economy seats on the Auckland-DFW flight would have a new trim and finish, wireless charging, water bottle storage and USB-C and AC power.
The aircraft had 244 seats, with 51 in business class, 32 in premium economy, and 161 in economy.
American said the A321XLR had 20 Flagship Suite seats and 12 premium economy seats.
Air New Zealand does not fly directly to DFW but does operate an Auckland-Houston service.
Those mid-January flights to Houston one-way were selling from $781 to $1160 in economy class and $7699 in the most expensive business-class seats.
American Airlines flights from Auckland to DFW for the same time were selling from $999 to $1079 in economy class and $6818 to $8671 in business class.
In April, American Airlines announced a streamlined bag-check service for its daily flight from Sydney to Los Angeles, but the offer was not extended to Auckland.
American is a member of the oneworld alliance, a rival to Air New Zealand’s Star Alliance.
North America’s market has been under pressure lately.
Data released by the International Air Transport Association (Iata) this week showed passenger growth for North American carriers slowing in May.
And a 1.7% year-on-year contraction was recorded in the US market.
“Economic uncertainty and a reduction in government travel have impacted the US domestic market,” Iata said this week.
John Weekes is a business journalist mostly covering aviation and courts. He previously covered consumer affairs, crime, politics and courts.