ITV Digital was a British digital terrestrial television broadcaster which launched a pay-TV service on the world's first digital terrestrial television network. Its main shareholders were Carlton Communications plc and Granada plc, owners of multiple licences of the ITV network. Starting as ONdigital in 1998, the service was rebranded as ITV Digital in July 2001.

Digital terrestrial television is a technology for terrestrial television where television stations broadcast television content in a digital format. DTTV is a major technological advance over analog television, and has largely replaced analog television broadcast, which had been in common use since the middle of the 20th century. Test broadcasts began in 1998 with the changeover to DTTV, also known as the Analog Switchoff (ASO) or Digital Switchover (DSO), which began in 2006 and is now complete in many countries. The advantages of digital terrestrial television are similar to those obtained by digitizing platforms such as cable TV, satellite, and telecommunications: more efficient use of radio spectrum bandwidth, provision of more television channels than analog, better quality images, and potentially lower operating costs for broadcasters.