Dormer had her breakthrough playing the role of Anne Boleyn on the Showtime series The Tudors (2007–08), which earned her widespread acclaim.

[8] Dormer chose to audition for drama schools and trained at the Webber Douglas Academy of Dramatic Art in London.

In 2007 and 2008, Dormer played Anne Boleyn in the first two seasons of The Tudors, for which she received highly positive reviews.

Robert Abele of LA Weekly wrote: "Natalie Dormer presents a painterly exquisiteness and complexity in her portrayal of Anne Boleyn... her enigmatic, time-halting loveliness is a boon for The Tudors, and damn near worth losing your head over".

[13] After her character's death at the end of the second season, The Boston Herald noted: "Dormer gave Anne Boleyn life, making her not just a beautiful schemer, but a rebellious, defiantly independent tragic hero in the tradition of Rebel Without a Cause and Cool Hand Luke... her departure from The Tudors leaves a tremendous void.

Dormer's Marple appearance aired in the US in the summer of 2009 as part of the PBS Masterpiece Mystery anthology series.

[15] In March 2010, Dormer debuted at the Young Vic theatre in London as Mizi in the play Sweet Nothings.

In The Observer, theatre critic Susannah Clapp praised the performances of the cast and wrote: "Natalie Dormer is lissome as a dirty, delightful gadabout, pushing aside an entire chess game to put down her hat".

[17] From 2012 to 2016, Dormer played Margaery Tyrell in the HBO fantasy TV series Game of Thrones.

In March 2012, Dormer worked at the Young Vic to play the title role in After Miss Julie by Patrick Marber.

[21] Her performance earned acclaim, with reviews describing her as "little short of sensational",[22] "outstanding",[23] and "the perfect Miss Julie".

[24] The online theatre magazine Exeunt says her portrayal of Miss Julie contained "all the anger, desire, wit, loneliness, merriment, melancholy, and desperation of the casts of several plays together... Dormer has more presence and eerie beauty than is apparent from her appearances on-screen, and she shape-shifts almost supernaturally between seductress, child, and tormentor.

In September 2014, Deadline Hollywood announced Dormer was cast in Screen Gems' action thriller Patient Zero, alongside Matt Smith and Game of Thrones co-star John Bradley.

[40] A February 2017 press-release announced Dormer was cast as schoolteacher Mrs Hester Appleyard in Picnic at Hanging Rock, an adaptation of the 1967 Australian novel of the same name by Joan Lindsay.

Dormer returned to the stage at the Theatre Royal Haymarket in October 2017 for the lead role in David Ives's Venus in Fur.

Nakedness is a good equaliser, and the shower scene also shows the tattoos on my character's body and makes it clear she is not quite who you think.

"[52][53] Following her audio work on Neverwhere, an August 2018 press release announced Dormer would narrate the audiobook for Pottermore Publishing's Harry Potter: A History of Magic.

Of the role, Dormer says she "always adored the Harry Potter books" and it was "fun to join the wizarding world family".

[58] In 2024, Dormer played Edie Hansen in the crime drama TV series White Lies, set in Cape Town, South Africa.

[67] On World Humanitarian Day in 2016, Dormer gave a speech at the United Nations headquarters to "highlight the plight of refugees".

Dormer highlighted the violence suffered by women and girls, then demanded that men and boys be "engaged" in the conversation.

[68] In 2017, returning to her feminist roots, Dormer went on holiday to Tanzania with the development and humanitarian organisation Plan International to ban child marriage.