Properties worth more than £15m have typically witnessed price falls of 22% since 2014 when stamp duty was increased for the top end of the market.
However, the price drops tempted international buyers into the market last year, according to Savills.
Sales in the capital’s so-called ‘super prime’ market increased by 43% between 2017 and 2018.
These transactions also helped boost activity for homes worth a slightly more modest £5m and higher, with sales increasing by 10% in this section of the market.
And for the first time since 2008, as much was spent in total on £15m-plus properties as on those worth between £5m and £15m, the estate agent found.
Lucian Cook, head of residential research at Savills, said: “The price falls we’ve seen in the central London market, when combined with the depreciation of Sterling, means the trophy properties of central London look relatively good value in an international context.
“Despite the backdrop of political uncertainty and a less welcoming tax environment, these figures are clear evidence that London remains an attractive place for a growing pool of international high net worth individuals to live and conduct business.”