BSkyB has signed up the 3 millionth subscriber to its high definition (HD) television service just over four years after it was launched in the UK.

More than 30% of Sky's total subscriber base, which stood at 9.86 million at the end of June, now watching in high definition.

Nearly 50 channels are available in high definition on the Sky digital satellite service, including BBC HD, ITV1 HD and five high-definition Sky Sports networks. Living became the latest broadcaster to join the HD platform today , with several more ITV channels due to join it before the end of the year.

More than 30% of Sky's total subscriber base, which stood at 9.86 million at the end of June, is now watching in high definition, a key driver in boosting the satellite broadcaster's average revenue per user.

Sophie Turner Laing, Sky's managing director of entertainment, news and broadcast operations, said the broadcaster had "recognised the potential of HD early", adding that the superior quality broadcasts had now "grown into something which our customers utterly love and now demand as standard".

However, the latest milestone also suggests that the growth rate of HD has slowed after a bumper second quarter boosted by the football World Cup. An extra 429,000 customers were signed up in the three months to the end of June, taking total HD subscribers to 2.94 million.

A slowdown was predicted by the BSkyB chief executive, Jeremy Darroch, who said in July that he expected to see a "pause for breath" in take-up of the new technology. The next set of subscriber figures, for the third quarter of 2010, will be announced at the end of October.

Sky's high-definition service launched in May 2006. High-definition channels are also available on Virgin Media, Freeview, the BBC and ITV's free-to-air satellite joint venture, Freesat.

Living HD, which broadcasts programmes including Britain's Next Top Model presented by Elle Macpherson, became the 46th high-definition channel on the Sky platform, following the launch of Good Food HD earlier this week.

Jonathan Webb, managing director of the Living TV Group, said: "Living is home to some of the glossiest UK and US programmes on television and they deserve to be seen in their pin-sharp HD glory."

Eden HD, ITV2 HD, ITV3 HD and ITV4 HD will all launch before the end of the year, taking Sky's total number of HD channels to more than 50. BBC1 will also be simulcast in high definition in its entirety for the first time this autumn.

Sky Sports' biggest HD audience to date was Manchester United's 3-0 win over Newcastle in their opening Premier League fixture of the season last month, which was watched in more than 800,000 homes.

Sky's next big marketing push will be 3D television, with the broadcaster set to launch Europe's first dedicated 3D channel on 1 October.