Prices in the capital were 1.9 per cent lower than in August, the Office for National Statistics (ONS) said.
The average residential property in London still costs in excess of half a million pounds – at £504,000 – yet is lower than in August, when the ONS reported an average of £514,000.
Across the UK as a whole, prices were up 10.4 per cent in the year to October, notably lower than the 12.1 per cent increase recorded in the year to September.
Despite falling in recent months, prices in London were still 17.2 per cent higher than in October 2013. In the rest of the south east region, prices were 11.9 per cent higher than a year earlier.
The data highlighted the plight of young people struggling to climb on to the housing ladder. Prices paid by first-time buyers were 12 per cent higher than a year earlier, while existing owners paid 9.7 per cent more on average than in October 2013.
The ONS figures are slower to be calculated than some private sector indexes, yet are based on real transactions that are put through a complex weighting system.