The downsizing will slash owner Johnston Press's annual rental bill for the Edinburgh-based titles by around two-thirds.
In December, this newspaper revealed that JP and the Scotsman titles were vacating the Irish-owned Barclay House on Holyrood Road after 15 years. The newspapers will be replaced as tenants by Rockstar North, the computer games firm behind the hit Grand Theft Auto series.
The group, which also publishes Scotland on Sunday and the Evening News, plus a string of smaller local titles, will occupy the top two floors - around 30,000 square foot - of Orchard Brae House, a refurbished triangular 1970s block opposite Stewart's Melville College.
The cost, at around £18 per square foot, is estimated at around £555,000 a year. This rental bill is around a third of the £1.5 million or so in annual rent that the newspaper group - which has debts of £302m - has paid to occupy the 75,000 sq ft Barclay House, at a cost of £20 per sq ft.
The refurbished Orchard Brae House has been owned by London commercial property investors Delancey since February 2011. Its website says the site offers "virtually column-free floor space with the upper floors delivering stunning panoramic views across the city".
According to Johnston Press's annual report and accounts, published last week, the group's underlying newspaper sales revenue, supported by cover price increases, was down 2.1% from £89.6m to £87.7m, while digital revenues grew by 19.4%, from £20.6m to £24.6m.