"It's fantastic to see the response by visitors who have visited the castle in their hundreds of thousands since the reopening of the palace, and to be recognised as the UK's favourite heritage attraction is a huge honour and testament to the hard work of all the team."
Which? members were asked to score the UK tourist attractions they had visited in the past two year for overall satisfaction and likelihood to recommend.
They were rated across several categories including value for money.
The survey is published in the September issue of Which? Travel magazine.