Yes of course, GoDaddy advertises on British telly so people type domains in their search engine. If listed on Afternic it will give the buyer your price, so of course UK domains sell via Afternic.
Sedo is a big platform for all European country code domains. Probably remains the biggest for UK domain sales I should think, at least by volume of domains sold.
Don't forget DomainLore for sales to other domainers at trade prices.