In 2012, the state-run company posted net profit of RON329.3 million.
According to the preliminary financial report, Trangaz registered an operational result of RON1.52 billion last year, up 11% from RON1.36 billion in 2012.
Transgaz said its total revenue rose 10% on the year, to RON1.56 billion, mainly due to a higher reservation tariff.
Overall expenditure rose by a similar percentage to RON1.13 billion, as the company had to pay higher taxes, due to a monopoly tax introduced by the Romanian government earlier in the year for electricity and natural gas transmission companies.
In its report, Transgaz said financial costs were up to RON141.6 million, from just RON26.8 million in 2012, largely due to a one-time charge of RON110.67 million in relation to the failed Nabucco West pipeline project, in which the company is a minority shareholder.
The Romanian government owns a 58.5% stake in Transgaz, which was listed on the Bucharest Stock Exchange at the beginning of 2008. Monday, Transgaz closed up 0.35% at RON184.1 a share. (EUR1=RON4.4905)