The parties to the transaction have agreed to maintain confidentiality regarding the price of the acquisition, Austrian Post said in a statement.
In October 2011, Austrian Post had already acquired 26% of Postmaster with an option of taking over the company in two years.
Founded in 2007, Bucharest-based Postmaster is already the leading alternative postal provider on the Romanian market, Austria Post said.
"The core business of the company is delivering direct mail items (advertising mail) weighing more than 50 gr. As a consequence, the company already has a very good starting position for the upcoming postal market liberalisation in Romania as of the year 2013 [..]."
Postmaster closed 2011 with a profit of some 4.3 million lei ($1.2 million/951,000 euro) on turnover of 41.8 million lei, the latest available data from Romania's finance ministry showed.
(1 euro = 4.5216 Romanian lei)