Do I have to pay Capital Gains Tax when I sell my main home?

Selling your only or main home is usually completely free of Capital Gains Tax thanks to Private Residence Relief, provided you've lived in it as your main residence for the whole time you've owned it (with some allowance for a final period before sale). The relief can be restricted if you've let out part of the property, used part of it exclusively for business, or have a large amount of land with it, or if it wasn't your main home for the entire period of ownership. If any of those apply to you, it's worth checking with an accountant before you sell, as you may still owe some tax on part of the gain.