The 483-year-old service, founded in 1520 as Correio Publico, has been valued on the Lisbon Stock Exchange at EUR831 million with the sale set of 105 million shares at EUR5.52 per share.
The Portuguese government has decided to privatise following the UK`s flotation and sale of 60 per cent of the Royal Mail in October, reported the UK`s Transport Intelligence.
The state needed to stem CTT`s declining revenues, down 3.5 per cent to EUR349 million first half 2013 and despite staff cuts of 939 fewer employees on the payroll during the six month period.
Potuguese Economics Minister Antunio Pires de Lima said privatisation would "maximise revenue for the state without compromising the strategic objectives of the company and paves the way for other companies to disperse capital or finance themselves by this means".