WASHINGTON — More than 35 percent of Americans have debts and unpaid bills that have been reported to collection agencies, according to a study released today by the Urban Institute.

These consumers fall behind on credit cards or hospital bills. Their mortgages, auto loans or student debt pile up, unpaid. Even past-due gym membership fees or cell phone contracts can end up with a collection agency, potentially hurting credit scores and job prospects, said Caroline Ratcliffe, a senior fellow at the Washington-based think tank.

“Roughly, every third person you pass on the street is going to have debt in collections,” Ratcliffe said. “It can tip employers’ hiring decisions, or whether or not you get that apartment.”

The study found that 35.1 percent of people with credit records had been reported to collections for debt that averaged $5,178, based on September 2013 records. The study points to a disturbing trend: The share of Americans in collections has remained relatively constant, even as the country as a whole has whittled down the size of its credit card debt since the official end of the Great Recession in the middle of 2009.

As a share of people’s income, credit card debt has reached its lowest level in more than a decade, according to the American Bankers Association. People increasingly pay off balances each month. Just 2.44 percent of card accounts are overdue by 30 days or more, versus the 15-year average of 3.82 percent.

Yet roughly the same percentage of people are still getting reported for unpaid bills, according to the Urban Institute study performed in conjunction with researchers from the Consumer Credit Research Institute. Their figures nearly match the 36.5 percent of people in collections reported by a 2004 analysis.