However, the figure was higher than the 48.1% increase in consumer prices forecast by Turkish economists.
Inflation fell by 2.97% month-on-month in September, the TUIK statistics agency said.
Turkey's central bank began raising interest rates last year in an attempt to combat rising prices.
Turkish President Recep Tayyip Erdogan has said inflation is trending lower.
"Our people will feel the slowdown more in the bazaars and in their shopping baskets," he added.
According to the Istanbul Chamber of Commerce, retail prices in Turkey's largest city Istanbul alone rose 3.9 percent month-on-month and 59.2 percent year-on-year in September.
According to official data, annual inflation in Turkey reached its highest in decades at 85% in October 2022.
It fell to 38.2% in June 2023, after which it rose again. In May this year it reached 75%, but in June it started to fall.
The biggest price increase in September was due to housing, which rose by almost 98% year-on-year, followed by education at 93.6%, and restaurants and hotels at 65.4%. | BGNES