We have been inundated with a wealth of fantastic photos after putting out an appeal for them on Facebook.
This gallery has been updated throughout the day as more and more pictures have been sent over!
MORE: Best World Book Day photos from 2021, World Book Day excitement grips Portsmouth as children become their favourite superheroes
Unfortunately due to the overwhelming amount of photos we were sent and time constraints, we have not been able to feature every single one sent to us today – despite hoping to be able to do so.
But we tried to feature as many as possible - and there are over 50 images in our gallery!
The gallery is at the bottom of this article – and make sure to click through all the pages!
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25. Snow White
Ariana aged 4 from Portsmouth as Snow White for World Book Day Photo: Tyrah Georgia Allen
26. Dennis the Menace(s)
Henley age 9 and Hardy age 5 both went dressed as Dennis the Menace to St. George’s beneficial school in Portsea for World Book Day. Photo: Dolly Cowlishaw
27. Mad Hatter
Brooke aged 8 from Waterlooville dressed as the Mad Hatter for World Book Day. Photo: Charlotte Waters
28. Bert
Alfie aged 7 from Waterlooville dressed as Bert from Mary Poppins for World Book Day. Photo: Charlotte Waters