The blue-chip SOFIX, which tracks the 15 most liquid shares on the Bulgarian Stock Exchange (BSE), edged down 0.60% to 318.68 points following a 0.17% decrease on Thursday.
The broader BG40, which includes the 40 most traded shares, lost 0.69% to 114.17 points after gaining 0.67% in the previous trading session.
Total turnover on the regulated market fell to 974,100 levs ($654,000/498,000 euro) from 1.1 million levs on Thursday.
Five of the 13 SOFIX components traded on Friday advanced, six fell and two ended flat.
First Investment Bank (FIBank) [BUL:5F4] led the SOFIX gainers, closing 2.12% higher at 1.635 levs as 1,500 shares changed hands.
Industrial group Stara Planina Hold [BUL:5SR] was the top blue-chip decliner, closing 6.96% lower at 2.23 levs in a volume of 2,399 shares.
The BG-REIT index, which tracks the performance of real estate investment trusts, ended 0.93% higher at 79.02 points after falling by 0.80% on Thursday.
The BG TotalReturn30, in which companies with a free float of at least 10% have equal weight, was up 0.22% at 256.47 points following a 0.34% decrease in the previous session.
The CGIX Corporate Governance index, which includes companies strictly applying corporate governance principles, lost 1.15% to 80.00 points. It fell 0.61% on Thursday.
(1 euro = 1.95583 Bulgarian levs)