Inflation fell to a five-year low of 1.2% last month as the supermarket price war kept a lid on the rise in the cost of living.
The Consumer Price Index measure of inflation dropped more sharply than expected from 1.5% the month before, the Office for National Statistics said.
Food and non-alcoholic beverages fell 1.4% year-on-year, the steepest drop since June 2002 and the fifth month in a row they have not risen on an annual basis.
The pound fell as the inflation drop made it less likely the Bank of England would need to take action to raise interest rates from their five-year low of 0.5%.
Liz Cameron, chief executive of Scottish Chambers of Commerce, said the September inflation figure was particularly important to the business community as it would be used by the UK Government to calculate any future rates increase south of the border.
“This is important to Scotland because the Scottish Government has continued its commitment to mirror changes to business rates levels in England,” she said.
