By Kathryn Mayer

A new study finds only 49 percent of workers in small businesses with fewer than 50 employees were offered and eligible for health insurance through their employer in 2010, down from 58 percent in 2003.

Larger firms are much more likely to provide health benefits. About 90 percent of workers in firms with 100 or more employees were offered and eligible for health insurance in both 2003 and 2010, according to the report from the Commonwealth Fund.

Low-wage workers in small businesses were the least likely to be offered and eligible for coverage: Just one-third of workers making less than $15 an hour in small firms were both offered and eligible to enroll in their employer’s health plan, compared to 70 percent of small firm workers making over $15 an hour.

Report coauthor and Commonwealth Fund Vice President Sara Collins says the report “highlights a nearly decade-long trend of declining health insurance coverage and rising costs for workers in small businesses, particularly those who make less than $15 an hour.”

“As a result, many people who work for small businesses can’t afford the health care they need or have medical bills they are unable to pay,” she says.

About half small business employees (45 percent) reported trouble paying medical bills in 2010, and 46 percent reported that they skipped needed medical care because of cost, the report says. That’s about ten percent higher than those workers working in larger firms.

Small business workers were also more likely to be dissatisfied with their health insurance, with 29 percent rating it fair or poor, compared to 16 percent of those at larger businesses. They also don’t have as much choice when it comes to health plan options.

But Commonwealth researchers say health reform should help address and solve some of these problems by offering premium tax credits to certain small businesses and by granting subsidies to many uninsured workers toward their purchase of health insurance beginning in 2014.

“The Affordable Care Act should mitigate this trend by improving the affordability and comprehensiveness of health insurance both for small-business owners who want to offer health benefits and for workers in small businesses who can’t get coverage through their jobs.”

The Commonwealth Fund is a nonpartisan research foundation that supports PPACA. Though they argue the law will help small businesses, opponents say the law will burden small businesses while raising taxes.