Every individual has a tax-free allowance known as the Nil Rate Band, which is currently frozen at £325,000. If you leave your main residence to your direct descendants (such as children or grandchildren), you may also qualify for the Residence Nil Rate Band, providing an additional £175,000 allowance. Married couples and civil partners can also transfer any unused allowances to each other, potentially creating a combined tax-free threshold of up to £1 million.