Powley shared the wonderful news on Instagram, revealing the couple were wed last week at Petersham Nurseries in Richmond, London.
"The day @douglasbooth and I got married, during the most love filled ceremony, in front of all our favourite people on this earth. I have no words to describe how happy I feel. I love you," she wrote.
Among those to congratulate the newlyweds was Bel's A Small Light co-star Liev Schreiber, who replied on Instagram: "Congratulations!!!! Sending both so much love!"
In a Vogue profile, Bel revealed that fashion brand Miu Miu created her wedding dress due to their preexisting relationship.
"I have worked closely with Miu Miu for nearly 10 years and have become very close to the brand," Bel said. "I always feel totally myself in their beautiful designs. When they agreed to make my wedding dress and party dress, I cried because it felt so special!"
The lavish ceremony is particularly impressive seeing as the couple planned the entire thing in just six months.
"I really recommend this because it forces you to make decisions quickly and doesn’t prolong the process," Bel insisted. "We didn't have one disagreement on anything, and we were a great team with the shared goal of throwing the best party full of love for all our friends and family who we adore so much.
"We knew we wanted it to feel relaxed, fun, and very London, which it definitely did when the heavens opened after lunch!"
Douglas popped the question in 2021 on Primrose Hill in London, which is the exact place where he'd first told Bel he loved her back in 2016.
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