Britain's biggest property website said the average monthly rent being asked is 11.8% higher than a year earlier, while the average monthly rent is now 19% or £177 higher than at the start of the pandemic.
Asking rents in the capital surged by 15.8% in the last 12 months, pushing the average asking rent there to a record £2,257 per month.
The latest figures, which cover the second quarter of 2022, suggest June saw the highest number of new rental listings coming to market of any month this year so far.
Rising rents continue to be driven by high tenant demand and a shortage of available rental stock, although there have been some recent signs of improvement, Rightmove added.
Despite this, the available rental stock is still down by 26% compared with last year’s levels, while demand is up by 6%, which means competition between tenants remains extremely fierce, Rightmove said.
Rightmove’s director of property science Tim Bannister said: "The story of the rental market continues to be one of high tenant demand but not enough available homes to meet that demand.
"Last year, we saw exceptional numbers of tenants looking to move and this year we have seen no let-up in this trend.
"Whilst stock levels are beginning to improve, with June seeing the highest number of new rental listings coming to market so far this year, the wide gap that has been created between supply and demand over the last two years will take time to narrow.
"Until then, this imbalance will continue to support asking rent growth. This has led to our revised forecast of (an) 8% rise in asking rents by the end of the year, up from 5%."
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