The three craft, designed for in-shore rescues, were unveiled this weekend, although they will be used by the charity at lifeboat stations across the country.
They have been purchased thanks to a donation from Warter Priory, the 12,000-acre shooting estate in the heart of the Yorkshire Wolds, which raised £162,000 during a three-day fundraising effort last year.
Two of the brand new, bright orange, D-class boats were named on Saturday in a ceremony at the boathouse in Whitby in front of 150 guests.
Warter Priory was taken over by Malcolm Healey, the former owner of Hygena Kitchens, and one of the country's wealthiest men, in the late 1990s. The massive East Yorkshire estate, with some 50 drives, is now run by his son Will.
The original aim was to raise enough funds to buy Whitby RNLI a new in-shore lifeboat.
But the target was smashed on the first day and enough money for two more was raised during the event, which included a clay shoot, auction and the annual Bush Beaters Ball.
One boat, named Warter Priory by the Duchess of Kent in recognition of their staggering fundraising efforts, will remain in service in Whitby. Dorothy Brighton named the second boat Eric Howland, after Will Healey's grandfather, who was a fisherman and served in the Royal Navy. It will join the RNLI’s relief fleet and will serve around the coast of the UK and Ireland.
The third lifeboat will be named at a later date and will go into service at Seahouses in 2018.
A crucial piece of life-saving equipment, the boats, which are smallest in the RNLI fleet, are used for rescuing people cut off by the tide or in difficulties in surf, as they can be taken into rocky areas and even beached.
Coxswain of Whitby RNLI Mike Russell, who has known Warter's head keeper Frank Croft for 30 years, is a picker-up on shoots on the estate with his dogs.
"Four years ago they raised £30,000 for new life jackets for the station, which means they have raised nearly £200,000, which is a lot of money. I know it's a pun but they really pushed the boat out.
"We're hoping to tag our website so every time it goes out to sea and performs a rescue it will be tagged to Warter Priory's site."
Being part of the RNLI, he says, is like being in a family, and for some crew members it goes back generations.
Among the guests was his uncle Ronald Frampton, who is nearly 90 and one of the last surviving oarsmen who manned a rowed lifeboat.
Mr Russell is retiring as coxswain and hanging up his pager after 16 years at Whitby, but will stay on as volunteer station chairman.
He said: "I'm not looking forward to retiring but I have a lovely, young crew and they deserve their chance.
"It goes right back in my family - my two uncles were part of the crew in the 1940s - and a lot of the lads are the same."
Mr Croft said: "Although we are far away from the sea, we know what an important charity the RNLI is. Anyone could get caught out when visiting the coast and to know they are there is a real reassurance. We couldn’t be prouder that our name will be on the new inshore lifeboat at Whitby."
Warter Priory's Churchillian connections
The former haunt of politicians and members of high society, Warter Priory was said to be a favourite of Winston Churchill. It suffered a steady decline after the Second World War and the house and gardens were demolished in the early 1970s. In 1998 Warter made the news when the owner, the Marquis of Normanby, of Mulgrave Castle, near Whitby, sold the estate for many millions to the East Riding-born multi-millionaire Malcolm Healey, who made his money from kitchens. The sale included Warter village, 63 houses, a park and sporting woodland. According to this year’s Rich List, Malcolm and his brother Eddie saw their collective wealth grow by £50m, keeping them in second place in Yorkshire at £1.48bn.