The UK has the world's highest level of digital TV viewers at nearly 70%, says a report by regulator Ofcom.
The entire UK is due to switch to digital by 2012
The study says 17.5m homes received digital channels by the end of 2005, with Ofcom expecting the 70% mark to be passed early this year.
The US is second with 55% but no other European country has passed 50%.
About 10.5m Freeview boxes have been sold, while the number of homes with Sky has overtaken those with only analogue channels for the first time.
More than 1.1m households took up digital TV in the last three months of 2005, more than in any other period.
A total of 2.7m homes were installed with digital TV in 2005, the highest ever annual amount.
By the end of the year, Ofcom says the UK had 7.7m Sky subscribers, 600,000 more than the number of households watching analogue on their main set.
Seven out of 10 homes with digital are watching terrestrial digital channels, while the cost of a Freeview box has halved since 2003 to £41 in 2005.
Ofcom says "digital penetration" has reached 80% in Wales, while the level rose over 2005 by 17% in the Border area, the first TV region to see analogue switched off in 2008, to a total of 80%.
The report said: "By the end of 2010, we expect around 95% of homes to have taken up digital TV of one form or another."
Nearly half of all TV viewing is still done through analogue terrestrial signals, down from about 65% in 2002.
Culture Secretary Tessa Jowell told Parliament earlier this month that reaching the 70% level was "an important landmark".