Employer Tax Costs. You should budget for Social Security/FICA taxes for each employee. These are currently 6.2 percent of the first $106,800 of compensation for each employee. Unemployment taxes amount to another 6.2 percent of $7,000 in pay.verage per hour employee cost is $30.07 in the US. hierarchy or promotion image by seema1 from Fotolia.com. Employers pay a substantial amount more than salaries for their employees. The US Bureau of Labor Statistics states that the average employee compensation averaged $30.07 per hour for March 2011.