Research by media regulator Ofcom will show seven in 10 households have gone digital, culture secretary Tessa Jowell has told Parliament.
This map shows analogue how switch-off will start in 2008 and end in 2012
"Ofcom will shortly publish data which shows the proportion of households which have gone digital has now reached 70%," Ms Jowell said.
Prime Minister Tony Blair has met representatives from the broadcasting industry to discuss digital switchover.
The change from analogue to digital TV will begin in 2008.
An Ofcom spokesman said its latest quarterly figures, to be published at the end of the month, were likely to show digital take-up was now "70% or thereabouts".
Ms Jowell called this "an important landmark".
At Tuesday's breakfast briefing at Downing Street, Mr Blair encouraged manufacturers and broadcasters to help boost consumer awareness in the run-up to analogue shutdown.
"Digital switchover is the right policy for Britain and we are delighted that it has the support of the industry," he said.
"A great deal of progress has been made so far, but it is vital that we continue to work together to ensure every region of the UK is switched to digital by 2012."
BBC chairman Michael Grade, Sky chief executive James Murdoch and Channel 4 chief Andy Duncan were among those who attended.
Also present were ITV's Charles Allen, Five's Jane Lighting and representatives from Tesco, Sony and Dixons.
At the meeting, Digital UK - the industry group which is co-ordinating the change to digital - said its own research had shown an increase in awareness of digital switchover.
World Cup preparation
"66% are now aware of switchover, up from 61% in November," a spokesman told the BBC News website.
It also said that a million of the 7.5 million households which have not yet converted intended to go digital in preparation for the football World Cup in June.
Another million intended to convert in the next 12 months, it continued.
Digital UK predicts the 70% penetration figure cited by Ms Jowell could rise to 80% by this time next year.
Its findings are based on a poll of 1,000 people conducted by research company BMRB.