The Taiwanese firm is locked in a dispute over "intellectual property" with the research and development company Ipcom.
It's believe HTC offered to sell their devices in the country but only with a workaround, and the Munich firm has said that the workaround was not put in place.
As a result, HTC devices now appear as "out of stock" for people in the UK.
A spokeswoman for HTC said: "As a leading innovator, HTC takes intellectual property issues very seriously.
"We are proactively investigating an infringement claim by a third party with respect to a single handset model."
The only place to buy HTC now is via Amazon and their own website.