Britain's annual Consumer Prices Index (CPI) inflation rate slowed down to 2.2 percent in September from 2.5 percent in the previous month, showed official data released on Tuesday.
"This is the slowest rate of inflation since November 2009, when it was 1.9 percent," the Office for National Statistics (ONS) said.
The slowdown in inflation came from gas and electricity price rises in 2011 falling out of the index calculation.
But the ONS warned the recent energy bill rises would bring up the inflation in the next couple of months.
According to the ONS, the retail prices index (RPI) annual inflation rate also eased to 2.6 percent in September, comparing with 2.9 percent in August.
The majority of the upward pressure for the RPI index came from an increase in the price of motor fuels.
Britain's consumer price index inflation rate is forecast to stand at 2.8 percent in 2012, and then ease to 2.1 percent in 2013, said a quarterly forecast report issued by Ernst and Young Item Club on Monday.
The report said the average earnings in Britain is expected to rise 2 percent this year, and further up to 2.8 percent in 2013, 3.2 percent in 2014 and 3.9 percent in 2015.