Geopolitical Tensions Hit Borsa Istanbul: BIST 100 Index Drops 3.20%

Geopolitical Risks Trigger Sell-off The BIST 100 index on Borsa Istanbul closed the trading day on February 19, 2026, with a sharp decline under the shadow of geopolitical risks.
Starting the day with a 0.56% increase at 14,340.28 points, the index reversed its course as news spread regarding a potential U.S.
intervention in Iran.
As selling pressure deepened due to increasing war concerns, the index fell 3.20% compared to the previous day, retreating to 13,804.21 points.
The total daily trading volume was recorded at 117.8 billion lira.
Sectoral Performance and Banking Index In the opening session, the banking index had gained 0.48% and the holding index 0.32%.
However, as geopolitical tensions dominated the market, these gains were replaced by sharp losses.
By the close, the banking index had lost 4.13%, while the holding index fell by 3.39%.
Among the sector indices, the only group to finish the day in positive territory was the financial leasing and factoring sector with a 0.8% increase.
The banking sector was recorded as the biggest decliner of the day.
Market Expectations and Technical Outlook Following consecutive record closes in January and a new historical peak in the second week of February, the BIST 100 index had recently shown a more cautious outlook due to profit-taking.
While AI-focused collaborations continue to support risk appetite in global markets, domestic markets remain under pressure from Middle East-sourced tensions.
Analysts point out that volatility in the markets may continue depending on geopolitical developments.