Belinda Anthea Stewart-Wilson is a British actress who played Polly McKenzie in The Inbetweeners.

Stewart-Wilson was born on 16 April 1971 in Kensington, the youngest of three daughters of Lieutenant-Colonel Sir Blair Stewart-Wilson, a British Army officer, and his wife, Helen Mary Fox. Stewart-Wilson grew up on military postings in the UK, Germany, and Austria before her family settled in London, her father becoming an Equerry to Queen Elizabeth II. She was educated at St Mary's School, Calne in Calne, Wiltshire and Hurst Lodge School in Berkshire, before completing a three-year degree in classical acting at the Webber Douglas Academy of Dramatic Art, in London.

Stewart-Wilson's first television role was in the series Shine on Harvey Moon, a show based in post-war London. Her next two roles were one-time appearances in the British sitcom Goodnight Sweetheart and playing a secretary in a TV adaptation of Agatha Christie's Poirot story The Murder on the Links.

From there Stewart-Wilson went on to play roles in British sitcoms Days Like These and Starting Out as well as Kiss Kiss, a feature film starring Chris Penn and Stellan Skarsgård. She also played Dina in La Passione, a feature film based on the life of Chris Rea, which opened the London Film Festival in 1997.

In 2004 she made an appearance in the long-running British medical drama Holby City, before moving on to two satirical programs: making an appearance in Look Around You, which won the Rose d'Or award for best comedy, as well as in three episodes of the 24-hour news-mocking Broken News.

Throughout 2007 and 2008, Stewart-Wilson worked on a number of television shows. Her most notable credits during this time period were the roles of Barbara Reynholm, the wife of Denholm Reynholm, in The IT Crowd, and Nikki in the TV series Jekyll alongside James Nesbitt and Gina Bellman. She also made an appearance in the mockumentary feature film Razzle Dazzle: A Journey into Dance, and played a cameo role in Stephen Poliakoff's Joe's Palace in a scene with Michael Gambon.

In 2007, Belinda played various roles in The Peter Serafinowicz Show, going on to appear in The Peter Serafinowicz Show Christmas Special in 2008 which was nominated for a Bafta for Best Comedy in 2009. A "best of" compilation was also aired in 2008.

Between 2008 and 2010, she played Will McKenzie's mother Polly in The Inbetweeners, the multi-award-winning sitcom which was nominated for a BAFTA Award for "Best Sitcom" in 2009 and won the BAFTA audience award in 2010. It also won most popular comedy programme at the National Television Awards in 2011. Stewart-Wilson also appears in The Inbetweeners Movie and its sequel, which were both box office successes. She also played the recurring role of Christine Johnson in the third series of the cult science-fiction show Primeval.

In 2010, she once again appeared in The IT Crowd, this time playing Victoria Reynholm, the wife of Douglas (Denholm Reynholm's son, played by Matt Berry, making her the daughter-in-law of her previous character), who mysteriously vanished two weeks into their marriage whilst washing the car.