The figure was 0.1 percentage point lower than forecast by economists polled by Poland's PAP news agency.
In August, the prices of consumer goods and services in Poland were 3.4 percent higher than in the same month a year earlier, according to the state-run Statistics Poland (GUS) agency.
In July, Poland's consumer price index stood at 3 percent, Statistics Poland reported.
Next year, Polish inflation is expected to average 2.8 percent, under the country's budget approved by the government on Tuesday.
The Polish central bank predicted in its latest Inflation Report, released on July 10, that inflation would average 2.9 percent in 2026, followed by 2.7 percent in 2027 and 2.2 percent in 2028.
(gs)
Source: IAR/PAP