The Hollywood couple have purchased the property in St Johns Wood which has been home to many celebrities including Sir Richard Branson, Lily Allen, Ewan McGregor and Sir Paul McCartney.
Jennifer and Nicholas will also apparently be assembling their own furniture, after Nicholas’s sister Clarista admitted that the pair were into feng shui.
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Jennifer Lawrence and Nicholas Hoult at the Monaco Grand Prix
"It's his first house. He's very excited and has been getting all his furniture from Ikea," she told The Sun newspaper.
"Nick has been big into feng shui, so in his room he has had branches, twigs with lights, the mattress and everything else on the floor - like water features and chairs - facing in the right direction."
The cute couple met in 2011 on the set of X-Men: First Class and dated for two years before splitting in 2013.
Their romance soon rekindled after they met again on the X-Men sequel, X-Men: Days of Future Past.
Jennifer has fallen in love with the English countryside, said one source, who said: "Jen loves the English way of life and as they are now serious again, it makes sense to look into buying somewhere."
They have spent several weeks looking for property in London and in Hampshire near Nicholas’s parents, and last week were spotted dining out with fashion designer Tom Ford.
The three enjoyed a meal with Tom at the Firehouse Club restaurant in London, and for the dinner date 23-year-old Jennifer sported a camel-coloured coat over chic black jumpsuit and accessorised her look with a metallic gold belt and black open-toe heels.
Speaking of his relationship with Jennifer, Nicholas said: "The privacy thing obviously changes but the rest pretty much stays the same."
Speaking to V Man Magazine, he said: "It’s like that thing whereby you don’t believe your own hype. Enjoy the good times but don’t get swept away with it."