Phillips was born in London and educated at Bryanston School and Robinson College, Cambridge, where she read social anthropology.
On the advice of a representative from Random House, Phillips submitted the second work to Dan Franklin, the publishing director of Jonathan Cape, who purchased the UK and Commonwealth rights.
She also has a regular personal blog on tumblr.com, which often includes reviews of literature, theatre, and film, as well as current television and radio.
She was a writer-in-residence for the charity First Story at Harris Academy Bermondsey 2009-10, and at Acland Burghley School in London in 2011.
[7] With Robert Hudson she wrote three series of Warhorses of Letters, a BBC Radio 4 comedy about the horses of Napoleon and Wellington starring Stephen Fry, Daniel Rigby and Tamsin Greig.
[19] It was originally optioned for television by Ben Stiller's Red Hour Productions,[5] and was made into a 2013 movie starring Sharon Stone, Alicia Silverstone and Christopher Walken by Big Beach Films.