Stormy Stan and the Hunstanton crew have been inviting families to enjoy the traditional seaside staple and raise funds towards their lifesaving work for donkey's years.
And there'll be plenty of sand to play with on the day this year, with a special area of the beach near the lifeboat station on Sea Lane roped off for competitors to sink their spades into at low tide.
Each will have their own area to work in, with mums, dads, grans and grand-dads encouraged to assist.
Stormy, who's partial to a spot of sandcastle building himself, has some advice to young builders.
'The trick is to add a bit of water to your sand, then squeeze it so you get a sturdy base to build on,' he said.
'And decorations are always a good way to make your castle stand out and catch the eye of the judges.'
Competitors will battle it out with buckets and spades for prize vouchers to spend in the lifeboat station's souvenir shop.
Registration is from 1.30pm, when parents will be asked to confirm their children can feature in photographs of the event to promote the work of the RNLI. Entry costs £1.
The competition will start at 2pm and last an hour. Please note the event may be cancelled in the event of rain.
Editor's notes
Hunstanton is one of Norfolk's busiest lifeboat stations, whose volunteers operate both the inshore lifeboat
Spirit of West Norfolk and search and rescue hovercraft Hunstanton Flyer.
They cover The Wash, a tidal estuary stretching for more than 100 square miles fed by five main rivers, along with parts of the north Norfolk coastline.
Like more than 200 RNLI stations around the coast of the UK and Ireland, the crew's lifesaving work could not be possible without the kindness of those who give donations or leave legacies to the charity that saves lives at sea.
RNLI media contacts
For more information call Chris Bishop, Hunstanton RNLI volunteer Deputy Lifeboat Press Officer on 07584 147219 or the RNLI Press Office on 01202 336789.
Key facts about the RNLI
The RNLI is the charity that saves lives at sea. Its volunteers provide a 24-hour search and rescue service around the United Kingdom and Republic of Ireland coasts. The RNLI operates 238 lifeboat stations in the UK and Ireland and more than 240 lifeguard units on beaches around the UK and Channel Islands. The RNLI is independent of Coastguard and government and depends on voluntary donations and legacies to maintain its rescue service. Since the RNLI was founded in 1824, its lifeboat crews and lifeguards have saved over 146,700 lives.
