This is the lowest proportion of buy-to-let purchases since the estate agency began collecting data in 2010.
It is a significant drop from the 15 per cent high recorded in the last quarter of 2019, which was also the highest level seen since Q4 2016.
The purchase total in the first quarter of 2020 was also down from the 11 per cent recorded the same time last year.
London has seen a sharp drop in buy-to-let purchases, making up just five per cent of residential purchases in the first three months of the year. This was down from the 18 per cent recorded in the last quarter of 2019.
Research from Hamptons released earlier this year showed the number of landlords in the UK market had dropped to its lowest level due to tax and regulatory changes. The research also noted a drop in the number of privately rented homes in the country.
Also, the current coronavirus pandemic has resulted in a shift in financial circumstances for landlords and their tenants, potentially impacting purchases.
A spokesperson for Hamptons said: “Landlords sprung back into action in December following the General Election result, but since then, they’ve retreated from the market once again.”