Donating through Gift Aid means charities can claim an extra 25p for every £1 you give. It will not cost you any extra.
Yes - I am a UK taxpayer and would like to gift aid my donation. I understand I must pay enough income tax and/or capital gains tax each tax year to cover the amount of gift aid that all charities and community amateur sports clubs claim on my donations in that tax year, and I am responsible for paying any difference.