The 19-year-old arrives at Anfield having reached the end of his contract at Stamford Bridge.
A compensation fee will be due to the Blues for a player nurtured through their academy, with a tribunal expected to rule on the size of the payment.
For now, Solanke is delighted to have linked up with his new employers and cannot wait to open an exciting new chapter in his career.
He told Liverpool’s official website: “It feels amazing and everyone has made me feel welcome already.
“Even just pulling on the training top, I was over the moon. Hopefully I can put on the shirt in the near future and make some good history here.”
Solanke arrives at Liverpool buoyed by World Cup glory with England’s U20 side.
He shone for the Young Lions as they became the first team since Sir Alf Ramsey’s 1966 heroes to claim a FIFA prize.
The talented frontman also scooped the Golden Ball as the best player in the competition, seeing him follow in the footsteps of the likes of Diego Maradona, Lionel Messi and Paul Pogba.
While impressing at international level, Solanke is still looking to make his mark on a domestic stage.
He did see regular football while on loan at Vitesse in 2015-16, but has left Chelsea having made just one senior appearance for the Blues.
Liverpool are hoping to further unlock his undoubted potential and be the ones to benefit from his future development.
Solanke will join an attacking unit at Anfield which has also been joined by Egypt international and fellow former Chelsea forward Mohamed Salah this summer.