Kotronias was awarded the titles of International Master in 1986 and Grandmaster in 1990 by FIDE.

Between 1998 and 2004, he represented Cyprus, but has since switched federations to become a Greek national player once again.

In seven appearances at the European Team Chess Championships, all played at board one, he made a score of +19 −13 = 26.

He also earned a bronze medal for his performance on the second board at the Dresden Olympiad 2008 and a gold medal for his performance on the reserve board at the European Team Championship 2013 in Warsaw.

[7] After leaving the River, Kotronias joined Syriza and was a candidate in the 2019 general elections.