UK CPI inflation dropped to 2.2% in October, a larger-than-expected fall that sent sterling to a two-month low against the dollar.
CPI inflation fell from 2.7% in September to 2.2% last month, the Office for National Statistics said, driven by falls in motor fuel and tuition fees.
Economists had predicted a fall to 2.5%.
The 2.2% headline figure matches the lowest level seen in recent years, reached in September 2012. The last time inflation stood below this level was in November 2009, when CPI was at 1.9%.
Sterling fell sharply against the dollar on the news, dropping by more than a cent to $1.5861, a two-month low.
RPI inflation, though no longer used by the ONS, also fell sharply from 3.2% to 2.6%.
The release comes a day before the BoE's quarterly inflation report, to be published tomorrow morning.
The report will outline the Bank's latest inflation and GDP forecasts.
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