The broadcaster released its annual report yesterday showing a net deficit of €19.7m after tax.
RTÉ cited a “range of large-scale special events” as contributing to the results, including general election coverage, Euro 2016, and 1916 centenary commemorations.
Other contributory factors included the knock-on effect of the €5m reduction in public funding in the 2014 budget and static income from the licence fee.
Furthermore, RTÉ’s “commercial revenue struggled” in the second half of 2016 as the “adverse impact of Brexit worsened”.
Dee Forbes, director general of RTÉ, said “2016 was a financially challenging year” for the broadcaster.
“Hosting and covering the most important anniversary in the history of the State coincided with a general election, a Northern Ireland assembly election, the UK EU referendum, a US presidential election, the Euros, Olympics, and Paralympics,” said Ms Forbes.
“The cost of the centenary events and coverage was an onerous one for RTÉ to absorb, while commercial revenue struggled for growth and public funding remained static.
“The failure to reform and modernise the current TV licence system is costing jobs.”