Lily Allen appears to be taking fashion inspiration from Taylor Swift.

The “Not Fair” singer was spotted at Duke of York Theatre in London Thursday sporting the same light blue lace corset dress the “Enchanted” hitmaker wore to Jack Antonoff’s wedding last weekend.

Allen, 38, posed outside of the venue – where she’s currently performing in “The Pillowman” – to show off the beautiful Erdem dress.

The frock, which features ruffles and an asymmetric hem, is retailed for $4,125 but is currently on sale for $1,040.36.

She styled her hair in a sleeked-back bun and topped off her look with an Anya Hindmarch clutch and high heels.

Paparazzi captured Swift, 33, wearing the same beloved dress last Saturday while attending Antonoff and Margaret Qualley’s nuptials in Long Beach Island, NJ.

The “Love Story” singer matched her look with Gucci stilettos, a vintage necklace from Cartier ($27, 250), Larkspur & Hawk earrings ($1,200) and a diamond finger bracelet from Jacquie Aiche ($5,435).

She also styled her hair down.

Swift’s attendance at the A-list wedding led to an uproar as fans caused a major street to shut down after she was spotted at the rehearsal dinner one night prior.

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Spies later told Page Six that the “Back to December” singer made a 15-minute speech during the reception, which was also attended by Channing Tatum, Zoë Kravitz, Lana Del Rey and more.

The “Cruel Summer” singer has been working with Antonoff, 39, for more than a decade since they collaborated on the 2013 track “Sweeter Than Fiction.”

He later produced hits for Swift’s albums from 2014 to 2022, including “1989,” “Lover,” “Folklore,” “Evermore” and “Midnights.”

Antonoff also helped Swift re-record “Taylor’s Version” of “Fearless,” “Red” and “Speak Now.”