Giselle Kennedy, 32, was told the devastating news that she had end-stage kidney failure in December 2019.
Best friend Leah Philbin, 31, was first to offer her organ and medics were shocked to discover the pair were a perfect match - before joking they could even be sisters.
The pair, from Nottingham, are now both recovering from the successful surgery which took place on May 26 this year.
Giselle, who works in communications, said she could not be happier and praised her friend s generosity for bringing them closer together.
She said: I will forever be in debt to Leah. She is an incredible person to bravely donate one of her kidneys and give me the gift of life.