Scotland's eight police forces are to be merged into one following an announcement next month, it is understood.
The policy is expected to be unveiled in September as the Scottish Government sets out its legislative programme.
Although a vote would be needed to introduce the legislation, the SNP government's majority in Holyrood is expected to see it approved.
A draft business case for the Scottish Government, obtained by The Sunday Herald newspaper, has also revealed the potential savings from the merger.
A single force would cost around £207 million to deliver during five years but save £390 million over that time. It would also save around £1.9 billion over 15 years.
But the Sunday Herald reported the move would also see £80 million of voluntary redundancy payments in the first five years, then a lowering of wages by £47 million and £66 million a year for officers and support staff respectively.
It is understood business plans were submitted to the Scottish Government covering other options for police force reorganisation outlined earlier in the year.
The Scottish Government said it would not be commenting on the details of the Sunday Herald story but released a statement.
A government spokesman said: "This government has delivered 1,000 additional officers to make our communities safer - helping drive crime to a 32-year low in Scotland - and our priority is to protect that strong frontline police presence.
"It is precisely because of those 1,000 additional officers that Scotland's police forces were able to deploy officers to help their English counterparts at short notice last week, for example, and we are committed to maintaining those numbers despite budget cuts from Westminster."