The Ministry of Defence spent a total of £10.1bn on IT between 1997 and 2009, figures revealed by junior defence minister Andrew Robathan have shown.
Expenditure peaked in the 2008-09 financial year, when £852m was spent on IT and £539m was spent on PFI (private finance initiative) service charges.
In total £8.35bn was spent on departmental IT, and £1.7bn was spent on PFI charges. PFI projects only started at the department in the 2005-06 financial year.
Robathan was answering a parliamentary question from Conservative MP Graham Evans.
The figures show annual IT spending grew until 2001-02, when it saw a sharp dip from £769m to £527m. After a few years of wavering between £628m and £738m, expenditure grew steadily from 2006-07 to its highest level in 2008-09.
The figures are not broken down into separate IT projects, but would include spending on the high-profile £5bn Defence Information Infrastructure project.