The company's revenue went up to 34 million levs last year from 30.1 million levs in 2020, Billboard said in an annual financial statement on Friday.
At the same time, Billboard's expenses rose to 33.4 million levs from 29.4 million levs.
Shares in Billboard last traded on the Sofia bourse on Thursday, when they closed 6.72% lower at 0.25 levs.
Billboard, established in 2001, offers wide format digital printing, offset printing and branding of vehicles, among other services.
(1 euro = 1.95583 levs)