The housing charity found that, in 55% of local authorities, typical rents from private landlords were more than a third of average take-home pay.
Campbell Robb, chief executive of Shelter, said: “We have become depressingly familiar with first-time buyers being priced out of the housing market, but the impact of unaffordable rents is more dramatic.
“With no cheaper alternative, ordinary people are forced to cut their spending on essentials like food and heating, or uproot and move away from jobs, schools and families.”
He called on the government to act to stabilise rents.
Shelter said that, in the ten years up to 2007, rents increased at one-and-a-half times the rate of incomes.
Private rents in 8% of local authorities in England are “extremely unaffordable” with average rents costing 50% or more of full-time take-home pay.
Just 12% of areas were affordable, with rents below 30% of take-home wages.
London boroughs are the most expensive, with the average monthly rent for a two-bedroom home in the capital standing at £1,360, almost two-and-a-half times the average in the rest of England of £568.
The highest private rent for a two-bedroom home was in Kensington and Chelsea, at £2,714 a month, while the lowest was in Burnley, Lancashire, at £394 a month.
Shelter said the least affordable local authority area outside London is Oxford, where typical rents account for 55% of average earnings.
