Countryside's monthly lettings index found Londoners were paying an average of £1,309 a month in the year to February, up from £1,295 the month before - that's £94 above the average monthly asking rent. In central London, that figure was £2,384, up from £2,461.
One in five found themselves paying more than asked, the report suggested - while at the other end of the scale, in Wales just one in 12 said they were paying over the odds.
Rents in the capital are now 34 per cent above their pre-recession record, compared with 12 per cent across the whole of the UK. The proportion of tenants able to negotiate money off their rent has fallen from 23.5 per cent in 2008, to just eight per cent now.
It wasn't just Londoners paying more than asked, though - Countrywide said across the UK, 12 per cent of lets were agreed at more than the initial asking price over the past year. The average tenant is now paying 99.9 per cent of the asking price - the highest figure since 2007.
“The combined effect of growing numbers of people renting and a lack of supply has seen tenants’ ability to negotiate diminish," said Johnny Morris, research director at Countrywide.
"Tenants are having to compete more often and with more people in order to rent the home they want, meaning they need to offer more money in order to push ahead of the crowd.”