PIPEX Internet Ltd. is an Internet Service Provider of the United Kingdom. It was established in 1991, originating from Unipalm, a software reseller, as the first commercial ISP in Britain. It initially operated with a 64k transatlantic leased line to UUNET. One of its first customers was Demon Internet. Later it merged with UUNET to form UUNET PIPEX and the Unipalm business was sold. UUNET PIPEX was taken over by Metropolitan Fiber Systems (MFS) which in turn was bought by Worldcom.
Some time later the UUNET name was revived and PIPEX was separated to become again a stand-alone company, owned by David Rickards and his family. It was announced in October 2003 that it will be purchased by GX Networks plc., for 55 million pounds. GX Networks will then rename itself to Pipex Communications plc to preserve the brand.