The 30-year-old brunette was undoubtedly the belle of the ball, with her dashing boyfriend Nico Jackson on her arm, as she dazzled in a floor-length black sparkling gown.
The black ensemble was complete with intricate embroidery on the bodice and featured a semi-sheer skirt which ran from mid-thigh to the ground.
A nude lining beneath the embroidered black material gave the impression that the dress was more revealing than it actually was.
A cropped black sparkling jacket finished Pippa's chic outfit, along with sparkling drop earrings and a black clutch bag.
Her brunette locks were swept off her face in an upstyle, in contrast to her sister Kate's trademark loose waves.
Pippa's stockbroker boyfriend made the perfect companion, looking as handsome as ever in a black tuxedo and bow tie as he posed for photographs beside his pretty girlfriend.
The duo were in good company at the charity ball, rubbing shoulders with fellow attendees such as Poppy Delevingne, Amber Nuttall, Tamara Beckwith and Downton Abbey creator Julian Fellowes.
Model Poppy brightened up the winter's evening with a colourful number, opting for a billowing striped pink and orange dress that she contrasted with an eye-catching leopard print coat. The beautiful blonde wore her hair loose over her shoulders.