More than 70 Jubilee tea parties will be held at Trust sites across the country on June 4, including Quarry Bank Mill in Cheshire, Anglesey Abbey in Cambridge and Powis Castle in Wales.
Specially created for the National Trust, the new Wallace and Gromit animation will be shown for the first time at the locations, as part of the Summer of Celebration campaign.
The film, titled A Jubilee Bunt-a-thon, features the hapless duo scaling ladders as they attempt to hoist bunting around their home at 62 West Wallaby Street and a magnificent Trust manor.
The National Trust said that the "green grass carpet" would be rolled out for the mini animation, which took 30 people three months to make. A behind-the-scenes film will also be shown.
Wallace and Gromit already have the royal seal of approval after the Duchess of Cornwall recently revealed that the characters are Prince Charles's "favourite people in the world".
"The National Trust and Wallace and Gromit are two of Britain's greatest treasures and we felt it fitting that in this summer of celebration we should bring them together," said Tony Berry, the visitor experience director of the National Trust.
"We are holding our very own premiere of Wallace & Gromit's Jubilee Bunt-a thon at our properties, it was made exclusively for the National Trust and we are really excited that it will encourage the nation to join us for an extra special Diamond Jubilee celebration."
Wallace and Gromit creator Nick Park said that the National Trust has a "special place" in his heart, as he based locations in movie Curse of the Were-rabbit on "childhood memories" of Trust houses.
"I have to pinch myself when I think how far Wallace and Gromit have come; from ideas in my head, to 'film stars' working with great organisations such as the National Trust, which the nation holds dear to its heart," he said.
"At Aardman we are thrilled that Wallace and Gromit have had a chance to explore all the Trust has to offer - from helping to put up bunting to enjoying their Wensleydale cheese platter at a picnic. Wallace and Gromit are in for a cracking summer at the National Trust.
"The National Trust has a special place in my heart from a childhood memory of completing a paint- by-numbers at Stourhead, to Montacute House, on which we based Tottington Hall in the Curse of the Were-rabbit."
Wallace & Gromit's Jubilee Bunt-a-thon will be shown on June 4 at fourteen National Trust properties as part of the Summer of Celebration Diamond Jubilee parties. For a behind-the-scenes look at the making of the Wallace and Gromit film visit www.nationaltrust.org.uk/wallaceandgromit.
The National Trust sites premiering the Wallace and Gromit film at the Jubilee tea parties include:
Beningbrough Hall, York
Powis Castle, Wales
Penrhyn Castle, Bangor
Basildon Park, Reading
Morden Hall Park, London
Quarry Bank Mill, Cheshire
Felbrigg Hall, Norwich
Anglesey Abbey, Cambridge
Springhill, Magherafelt, Northern Ireland Castle Ward, Downpatrick, Northern Ireland