The 26-year-old Matildas captain — who scored five times in this year’s World Cup as the Australians reached the last 16 — signed a two-and-a-half-year contract with the Women’s Super League club.
Kerr, who has been a mainstay at Perth Glory since 2014 while also playing for Chicago Red Stars in the United States, will be available for selection from January.
According to a report in the Sydney Morning Herald last week it is believed Kerr — who also attracted interest from Lyon, Bayern Munich and Real Madrid — will earn worth more than £467,000 ($600,000) a year, not including potential bonuses.
However, Kerr — the all-time leading scorer in the Australian and American leagues — said she felt Chelsea were a team that had laid a solid base for winning silverware.
“The WSL is the best league in Europe,” she said.
“I want team success and I don’t want it to come easy.
“I feel Chelsea have been building something special over the years and I want to be a part of that — I want to lift some trophies.”
Chelsea manager Emma Hayes said Kerr’s decision showed that they were a marquee club.
“The fact she chose Chelsea when she could have gone to any club in the world is a testament to the players and the staff here,” said Hayes.
“Sam has proved time and time again in the NWSL (National Women’s Soccer League in the USA) that she is a prolific goalscorer.
“She’s won the golden boot many times and she’s a player that can make things happen, but she’s also a fantastic team player.
“She saw this as the best place for her to grow and take the next step in her career. That’s a wonderful compliment to us all.”
Kerr, who has twice been shortlisted for FIFA Player of the Year and is one of the sport’s biggest names, made her debut for Perth Glory at 15 and spent four years at the club before moving to Sydney FC.
She returned in 2014 for a second stint.
Known for her pace, agility and heading ability, as well as her trademark backflip goal celebrations, she has also played in the United States since 2013, first at Western New York Flash, then Sky Blue FC in New Jersey and Chicago.
Kerr is the ninth player from Australia to play in England, following the likes of Emily Gielnik (Liverpool), Tanya Oxtoby (Doncaster Belles) and Caitlin Friend (Notts County).
