The average small-business CEO earns less than half of what the head of a midsized business makes and about a quarter of the salary of a CEO at a large company, according to a survey by Salary.com, a Waltham, Mass.-based payroll services firm.

In a survey of 2,237 firms with under 500 employees, the median salary for CEOs was $233,500, while the median salary for the top execs was $500,000 at companies with 500-5,000 workers and $849,375 for those with more than 5000 workers, according to Salary.com.

"As companies grow, so do the responsibilities and paychecks of their executives," Christine Midwood, director of survey services for Salary.com, said in a statement. "To attract and retain the best talent, it’s important for smaller companies with smaller budgets to emphasize non-cash advantages such as company equity or work/life balance."