A Scotland Yard spokesman said: "Operation Weeting (the hacking probe) has been in contact with or been contacted by 2,037 people, of which in the region of 803 are 'victims', whose names have appeared in the material.''
The new, lower total was first reported by the Murdoch-owned Times newspaper.
Phone-hacking victims have included celebrities including actors Hugh Grant and Sienna Miller, as well as aides to Britain's royal family.
The scandal exploded in July when it emerged that the News of the World had also hacked the phone of Milly Dowler, a British schoolgirl who was murdered in 2002, and deleted some messages on her voicemail.
Murdoch closed the tabloid that same month, while the row also claimed the jobs of two top Scotland Yard officers and several Murdoch executives.
But the Guardian reported Saturday that police now believed the News of the World was not responsible for deleting one particular voicemail on Dowler's phone, which caused her family to have false hope that she was alive.
Dowler's parents last month told an inquiry into the scandal that when the key voicemail was deleted shortly after her disappearance they had briefly thought it meant she was still alive.
They said police had later told them the paper had erased it to make space for more messages.
Their emotional testimony to the inquiry made front-page headlines in Britain and added to the sense of outrage against Murdoch's media empire.
But the Guardian said it now appeared that particular message had been deleted automatically by her phone after it was listened to - and that it may not have been the News of the World that had listened to it in any case.
The Guardian, which helped uncover the phone-hacking scandal, said the tabloid was still believed to have deleted other voicemails belonging to the murdered teen.
Eighteen people have been arrested over the hacking scandal since the investigation was reopened in January, including Prime Minister David Cameron's former media chief Andy Coulson, a one-time News of the World editor.
-AFP