Margot goes undercover for her birthday

She's becoming one of Hollywood's most bankable stars, but Margot Robbie isn't here for OTT birthday parties.

Despite regularly being seen on red carpets around the world, the Suicide Squad star opted for a more low-key party when celebrating her 27th birthday over the weekend.

Instead of throwing a lavish shindig filled with famous friends, Margot and husband Tom Ackerley flew under the radar at a local music festival outside of Central London, enjoying the tunes with a bunch of close friends, according to The Daily Telegraph.

It's no surprise Margot chose an intimate celebration, with the actress is known for her down-to-earth ways, regularly opting to stay with family and friends when returning to Australia instead of expensive luxe hotels.

Margot's music festival birthday comes after the Gold Coast native was seen partying it up with model Cara Delevingne at Glastonbury last weekend.

However her attendance at the iconic UK music festival wasn't without controversay, with fans slamming Margot after she appeared to share a sponsored post on her Instagram page.

Sharing a photo with her pals, Margot tagged gumboot brand Hunter in the snap and wrote "#ad" as caption.

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Margot soon deleted the hashtag instead opting for a more suitable caption of "#glasto", prompting questions and backlash about the missing hashtag from fans.

The star also uploaded another hashtag-free shot from her music-filled weekend, of a half-body shot with the gumboots in full view.

Fans were quick to comment on the post with many asking "Is this an advert?" underneath the snap.

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