Average rents for single rooms across the UK increased at a faster rate than those in London, according to spareroom.co.uk.
The rental site says UK rents – excluding the capital – were over 5% higher in the first quarter of this year when compared with the same period in 2015.
In the capital, rental growth for single rooms was stunted at just 1.63%, the firm's Q1 2016 Rental Index shows.
The biggest rental increases in Q1 were recorded in Luton, Swindon, Reading and Bristol, while the cheapest average rents for single rooms were in Belfast, Bradford, Dundee and Sunderland.
SpareRoom says that comparing Q1 2016 with the same period last year, supply of rental rooms increased by 25%.
It suggests this increase was down to a glut of additional properties and rooms entering the market in the first few months of the year as landlords and investors raced to beat the stamp duty surcharge deadline.
The index shows Belfast and Harlow, Essex as having the highest competition for rooms, with an average of nine people searching per listing in these areas.
“The first quarter of 2016 saw some respite for renters, thanks to an upturn in supply as buy to let investors rushed to complete ahead of the stamp duty increase," says Matt Hutchinson, director of SpareRoom.
He says, however, that the market is still 'groaning' under the weight of demand, particularly in London's satellite towns.
"Even cities like Manchester and Birmingham, which offer some of the highest levels of supply for renters in the UK, are massively oversubscribed with six tenants competing for every room," he adds.
The Office for National Statistics recently revealed that the average rent paid by private tenants across Great Britain increased by 2.6% in the twelve months to April.
Meanwhile, the Association of Residential Lettings Agents reports that supply and demand were both down year-on-year in April.