Istanbul Stock Exchange Falls to Lowest Level Since December 2025 Amid Investment Fund Crisis

The BIST 100 index on the Istanbul Stock Exchange fell below the 11,000-point level for the first time in 2026, marking its largest decline in recent history following an investment fund crisis, according to available data.

The index closed yesterday at 11,116 points, down 0.92%, marking six consecutive weeks of decline for the first time since 2008. Since the fund investigation began, BIST 100 has lost approximately 25%, while losses among more than 500 small-cap stocks outside the index exceeded 50%. Integral Yatırım noted that this broad-based collapse affecting 95 stocks over Wednesday and Thursday had not been witnessed on the exchange since March 2020.

Portfolio manager Ibrahim Ethem Avcan clarified that more than 60 companies trade daily at the minimum price limit with a 10% decline, while total losses on the exchange reached approximately 100 billion dollars.

The crisis was exacerbated by crude oil prices rising above 114 dollars per barrel alongside uncertainty surrounding fund liquidation operations. Its repercussions have extended to listed companies; Borlease Otomotiv, listed in 2023, announced its inability to pay a financing bond due on October 27, while Alnus Yatırım—one of the brokerage firms implicated in the fund case—defaulted on bonds worth 200 million lira, in addition to Tarfin's disclosure on Wednesday of its payment default.

The proportion of those intending to invest their savings in the stock exchange declined from 3.2% in September to 1.8% in October according to Turkish Central Bank data, while interest in investment funds denominated in lira fell from 1.8% to 0.9%, with investor confidence shifting toward real estate, automobiles, and gold.