The stunning siblings splashed out £1.56million on the former Hollywood Hills abode of Cara's 'Suicide Squad' co-star because they want a Los Angeles base.
A source told The Sun: ''Cara and Poppy are both spending more and more time in LA, and decided the time was right to have a base out there.
''Being so close, the idea of sharing a house seemed a natural step and they're really excited to get hold of the keys and bring their own vibe to the place.''
The two-bedroom home two kitchens, a swimming pool and even a recording studio.
Cara, 24, and Poppy, 31 - who is married to James Cook - both started their careers as models before branching into acting.
Cara is currently starring in blockbuster 'Valerian and the City of a Thousand Planets' alongside Rihanna, while Poppy landed roles in 'King Arthur: Legend Of The Sword'' and 'Kingsman: The Golden Circle'.
Speaking after Poppy landed the 'Kingsman' role, a source said: ''It is her first lead role and she will be starring opposite some of the biggest names in the film industry.
''It speaks volumes that director Matthew Vaughn personally chose her for the part too. He had heard on the grapevine that Guy Ritchie was really impressed with her on King Arthur.
''She'll be playing the baddie and has been getting her teeth stuck in on set already.
''The Delevingnes are in huge demand in Hollywood right now, and this is a pretty big deal for Poppy in the wake of Cara's success in 'Suicide Squad'.''
What's new in the music world this week?
Watch three incredible live performances from Discovr.TV.
Don't miss the K-pop titans' return to Europe.
Listen to Alex Bayly performing 'Animal'.
Two weeks ahead of Independent Venue Week, Dry Cleaning made 'Britain's Best Small Venue 2015' (NME) the second port of call on their 2020 tour.
'Leave Home' was released on this day (January 10th) in 1977.
For their last gig of the year, The Libertines came back to their adopted hometown of Margate to finish off their latest tour.
Arthur grew up as a peasant on the streets of Londonium having escaped the terror...
For those who knew him, Gary Unwin (better known as Eggsy to his friends), was...
Arthur might have an extraordinary destiny, but after his birthright was taken from him at...
For the most part, Arthur has taught himself all the life lessons he knows, he...
Legal radio stations in 1960's Britain weren't exactly what you'd call interesting to listen to...