The London club have reportedly signed the American defender to join the world record for female footballers.
Chelsea have signed United States defender Naomi Girma from the San Diego Wave in what is considered the world's most expensive female soccer player.
Girma is believed to have cost Chelsea 900,000 euros ($1.1m), surpassing the world record 685,000 euros ($718,976) paid by Bay FC for Racheal Kundananji in February 2024.
The 24-year-old was unveiled on the pitch by the Women's Super League champions during Sunday's game against Arsenal at Stamford Bridge.
“I am happy and very happy to be here. It doesn't feel real,” Girma told Chelsea's website.
“There are many things about Chelsea that made me want to come here, the culture, the winning mentality, the staff and the players. It's a great place to learn and grow.”
Girma has become Chelsea Women's coach Sonia Bompastor's first signing of the January transfer window.
He is being watched by Bompastor after Chelsea defender Kadeisha Buchanan suffered a hamstring injury that could keep her out for the rest of the season.
The fee surpasses the previous British record set when Chelsea signed striker Mayra Ramirez from Levante for 384,000 euros ($403,046) a year ago.
Girma played every minute of the US's Olympic victory in Paris last year and was named the US female player of the year in 2023.
Chelsea women's director of football Paul Green said: “Naomi is a world-class defender who is now entering the prime of her career.”
