Renters' paychecks hit hard in priciest cities

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A banner and sign advertise apartments for rent in San Francisco.

San Francisco may be the priciest U.S. city for renters, but apartment dwellers in New York and Los Angeles pay an even bigger share of their paychecks—more than half—to the landlord each month.

Renters in St Louis, meanwhile, spend less than a quarter of their paychecks on housing, according to the latest data from real estate website Trulia.

And most renters in the priciest cities shell out an even bigger share of their paychecks, as rent hikes continue to outpace salary increases. Last year, renters saw the biggest hits in Denver (up 14 percent), Oakland (12 percent), San Francisco (11 percent) and New York (9 percent).

The increase in rents are being fueled, in part, by strong demand for apartments thanks to a stronger job market that is helping millennials stranded by the Great Recession in their parents' basements move out on their own, according to Trulia Chief Economist Jed Kolko.

"But apartment construction has been booming for the past couple of years," he said. "That will continue to bring new rentals onto the market in 2015 and could cool down those rent increases."

Rental demand is also being helped by the tepid pace of home buying among younger households. Some are reluctant to take on the responsibility of a mortgage; others are having a hard time qualifying for a loan because of high student loan debts or tougher credit standards since the housing collapse.

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Whatever the reason, the rental boom has produced a major windfall for landlords. Last year, landlords collected some $441 billion from Americans renters—up $20.6 billion, or about 5 percent, from 2013, according to separate data from real estate site Zillow. The increase represented both higher rents and more renters.

Renters in the Bay Area, both the San Jose and San Francisco metro areas, saw the largest jump in cumulative rent paid in 2014, up 14.4 and 13.5 percent, respectively.

Of the top 50 markets, landlords in the New York metro area took in the biggest piece of the overall rental pot—some $50 billion altogether—followed by Los Angeles with $34 billion.

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"Next year, we expect rents to rise even faster than home values, meaning that another increase in total rent paid similar to that seen this year isn't out of the question," said Zillow Chief Economist Stan Humphries. "In fact, it's probable."