Film fans in the US will soon be able to download major movies on the same day the DVD of the films become available to buy in shops.
Brokeback Mountain is one of the first films to go on offer
Online film services Movielink and CinemaNow will begin selling downloads such as Brokeback Mountain this week.
Up until now, both services only offered digital movie downloads for a rental period only.
The head of CinemaNow, Curt Mavis, described the move as "one giant step for digital distribution".
Movielink and CinemaNow have both signed download-to-own deals with major Hollywood studios such as Universal Pictures, Warner Brothers and Twentieth Century Fox.
"This is an endorsement that digital delivery of high value content has finally arrived," said Jim Ramo, head of MovieLink.
Both Marvis and Ramo said they expected all major studios to sign deals with them soon if they had not done so already.
Both services will offer old titles alongside new movies.
The downloads will be software protected so they can not be burned on to DVD discs and replayed on DVD players.
In the past, major Hollywood studios have been reluctant to offer new films for sale in this way because of piracy fears.
A similar service was launched in the UK by the AOL website earlier this month and will be available from 10 April.
In February, another UK website, Wippit, started offering permanent downloads - but only independent movies are currently available.