The young royal started at Willcocks Nursery School in Kensington this week, following in the footsteps of his big sister, Princess Charlotte, five, who also attended the same nursery.
WATCH: William and Kate's festive outing with George, Charlotte and Louis
The adorable image was taken at Kensington Palace on Wednesday by mum Kate, shortly before Louis left for his first day at nursery.
It shows Louis, dressed in a navy jumper and shorts, beaming at the camera as he sits on a red £190 Frog Tadpole balance bike. He looked ready for his big day ahead as he also carried a navy rucksack.
Louis was probably welcomed by the sight of his favourite toy or a picture from home when he arrived at Willcocks, a gesture for all new children to help them make a smooth transition from home to school.
Louis posed for a photo on his balance bike before starting nursery
Willcocks Nursery School, which charges £3,400 per term for children attending morning school, and £2,250 per term for afternoon sessions, is a short drive from the Cambridges' London home, Apartment 1A at Kensington Palace.
It is likely Kate was invited into the nursery for her first "stay and play" session with Louis, where the parent gradually spends more time away from their child until they are happy to be apart from their mother or father for the whole day.
Louis' older siblings, Prince George, seven, and Princess Charlotte, five, currently attend Thomas's Battersea school in south west London.
Kate's photo of the Queen and Prince Philip with their great-grandchildren
The Duchess of Cambridge, who has been taking the official portraits of her children since the birth of Princess Charlotte in 2015, also shared a previously unseen image of the Queen and the late Duke of Edinburgh with seven of their great-grandchildren last week.
The family snap was taken at Balmoral Castle in 2018 when Prince Louis and his cousin, Lena Tindall, were less than a year old.
George, Charlotte and their cousins, Savannah and Isla Phillips, and Mia Tindall also featured in the photograph with their great-grandparents.
William and Kate leave hospital with newborn Louis in 2018
Prince Louis was born at the Lindo Wing of St Mary's Hospital in Paddington on 23 April 2018.
The tot's full name was announced as Prince Louis Arthur Charles just a few days after his birth, and he is fifth in line to the throne behind sister Charlotte.
HELLO!'s selection is editorial and independently chosen – we only feature items our editors love and approve of. HELLO! may collect a share of sales or other compensation from the links on this page. To find out more visit our FAQ page.
Make sure you never miss a ROYAL story! Sign up to our newsletter to get all of our celebrity, royal and lifestyle news delivered directly to your inbox.