Excluding London, the average rental price in the UK was noted at £838 in December, a 5.7% rise annually.
Looking to the capital, the average price per month to rent a property in London was £1,576 in December 2020, 86% higher than the rest of the UK.
However, between December 2019 and December 2020, the average price to rent a property in London dropped by 4.5%.
Nine of the 12 regions monitored by HomeLet outlined an annual increase in rental prices, with the South East noting the greatest rise at 10%.
Hammersmith, Fulham, Kensington and Chelsea recorded the join largest decline in average rental prices year-on-year at 10.2%.
In contrast, Brent saw a 7.7% increase over the same timeframe.
Andy Halstead, chief executive at HomeLet, said: “At a national level the latest data shows a continuation of the trends we’ve seen emerging since the national lockdown ended, with rents for new tenancies increasing across the UK, with the exception of London.
“In the regions surrounding London, the annualised variations in rental values for new tenancies looks significant.
“In reality this is a theme that we’ve seen grow gradually month on month, since July 2020.
“The trends we’ve seen in the past 12 months highlight the responsiveness of the private rented sector, and the crucial role it plays in supporting the changing needs of a significant proportion of households in the UK.
“Whilst overarching optimism remains strong for 2021, with vaccines being rolled out for COVID-19, we can still expect a year that will be disrupted by the impact of the virus.
“With the new national lockdown and the prospect of additional restrictions to help curb the impact of the virus and new variants, we can expect the demand for certain property types and locations to grow, pushing rents up.”