Data from national statistics agency INEI showed the key index based on the metropolitan region of Lima slowed to its lowest level since August 2021, when it stood at 4.95%.
On a month-to-month basis the Lima Consumer Price Index, Peru's inflation benchmark, inched up 0.02% in September, well below the 0.38% increase in August.
The figures are a boost to Peru's bid to wrestle inflation back to the central bank's official target of 2%, plus or minus one percentage point.
The monetary authority kept its benchmark interest rate unchanged in August at 7.75% for the seventh month in a row after an aggressive series of hikes started in August 2021, part of its efforts to tame high consumer prices.
INEI said in a statement that inflation in September was driven by price rises in transportation, restaurants and hotels, and miscellaneous goods and services, which rose 0.56%, 0.43% and 0.32%, respectively.
The world's second-largest copper producer has been grappling with poor weather, lower private investment in mining and anti-government protests staged earlier this year, which has led the government to slash its forecasts for economic growth.
(Reporting by Diego Ore in Mexico City and Jose Joseph in Bengaluru; Editing by Drazen Jorgic and Aurora Ellis)
