BIST 100 fell 5.54% to 13,122.58 points as 17 stocks closed at the floor price

Istanbul Finance Center towers at dusk, Ataşehir — Istanbul Finance Center, Ataşehir (September 2023)Photo: Acode37 / Wikimedia Commons · CC0 · Source

Location: ISTANBUL

The BIST 100 index closed at 13,122.58 points on 16 September 2026, down 769.72 points or 5.54%. According to Takvim, trading volume came to 262 billion lira; the banking index lost 6.38%, the holding index 6.48% and the leasing and factoring index 9.74%. The index swung between 12,817 and 13,877 points during the session and 17 stocks traded at the floor price. It was the index's third consecutive day of losses: the sessions of 14, 15 and 16 September all closed negative.

Behind the sell-off were the US Federal Reserve's decision on 16 September to raise the policy rate by 25 basis points to a range of 3.75-4.00% and the messages it gave after the decision; GlobalSecurity reported that the Fed referred to tension in the Middle East in its reasoning. The dollar closed 16 September at 48.6520 lira and the euro reached 55.8063 lira; the dollar is up about 13.12% from 43.0312 lira at the start of the year. The index opened 17 September down 1.32% at 12,948.83 points; in analyst commentary reported by Takvim, it was suggested that selling pressure could continue in the days ahead in a more moderate form.

Talay assessment

Bottom line

A 5.54% loss in a single day and 17 stocks hitting the floor show how dependent Turkish assets are on global risk appetite at a moment when dollar rates have begun to rise following the Fed's increase. The concentration of losses in banking and leasing points to a shock arriving through the funding cost channel. While the Fed maintains its tightening signal, the most likely path is a market under continuing pressure with high volatility.

Likely effects

Turkish banking sectorNegativeWeeks
Rising dollar rates increase banks' external funding costs; the 6.38% fall in the banking index and the 9.74% fall in the leasing index show this to be the most fragile link.
The Turkish liraNegative1–6 months
The dollar rising to 48.65 lira, a gain of 13.12% since the start of the year, pushes imported input costs and the inflation path higher and narrows the CBRT's room for cuts.
Foreign portfolio flowsNegative1–6 months
The Fed moving to increases may accelerate outflows from emerging markets; if the risk premium rises in high-inflation countries such as Türkiye, equity and bond inflows weaken together.

Possibilities, ranked

1
Pressure with high volatility50%
The index fluctuates in a 12,800-13,400 band with sharp daily moves; banking sets the direction.
Watch: Consecutive closes below the 12,948.83 level of the 17 September open
2
The sell-off deepens30%
The Fed signals a further increase, the rise in the dollar against the lira accelerates and the number of stocks at the floor rises again.
Watch: The dollar moving clearly above 48.65 lira and a new circuit breaker being triggered
3
Technical recovery20%
The Fed's message softens and oil falls back; the index recovers part of its three-day loss.
Watch: Consecutive positive closes in the banking index and volume falling below 262 billion lira

Probabilities are calibrated judgement based on the sources, not measurement, and are revised as new information arrives. Not investment advice.

Market reaction

Indicators affected

USD/TRY close▲ 48.65 TL
Banking index▼ −6.38%
Stocks at the floor price▼ 17 stocks

Historical context