Charlotte, who is affectionately known as Lottie to her family, can be seen grinning at the camera in a pretty floral, puff-sleeved, button-front navy dress from children's clothing company Rachel Riley, in the photo taken by her mum Kate.
The image, which comes shortly after the Cambridges starred in a sweet home video, was released by Kensington Palace with an accompanying statement that read: "The Duke and Duchess of Cambridge are very pleased to share a new photograph of Princess Charlotte ahead of her sixth birthday tomorrow.
"The photograph was taken by The Duchess this weekend in Norfolk."
WATCH: Birthday girl Princess Charlotte's cutest moments
Charlotte is the middle child and only daughter of William and Kate. She was born at 08:34 in May 2015 in the Lindo Wing of St Mary's Hospital in Paddington, London – the same hospital where Kate gave birth to her two sons, Prince George and Prince Louis.
Her name was announced as Charlotte Elizabeth Diana a couple of days later, with her middle names in tribute to her great-grandmother, the Queen and paternal late grandmother, Diana, Princess of Wales.
Charlotte was baptised at St Mary Magdalene Church in Sandringham, Norfolk in July 2015. Her parents' cousins, Laura Fellowes and Adam Middleton are among her godparents, as well as their friends Thomas van Straubenzee, James Meade and Sophie Carter.
The young royal turns six on Sunday
The Princess made history at the age of two when her younger brother Louis was born in April 2018. Charlotte became the first female royal to benefit from the change of succession law, which states that girls will not be overtaken by any future younger brothers. This meant that she retained her place as fourth-in-line to the throne, while Louis is fifth.
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Floral cotton dress, £20, Monsoon
Kate took this birthday photo of Prince Louis on his way to nursery
Last year while she celebrated her birthday in lockdown, Charlotte joined her family in making batches of fresh pasta and filling at least a dozen bags to deliver along with food packages to elderly and vulnerable people living near Sandringham.
The Cambridges were doing their bit to help their local community amid the pandemic, and the series of photos taken by mum Kate showed Charlotte carrying food parcels and knocking on people's doors.
The royals were taking part in Sandringham Estate's volunteering initiative, which saw staff prepare and deliver meals to isolated people living in the area. Around 1,000 meals were made and delivered in the first week alone.
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