Is there a Private contractor fee?

[4nature]

I owe a lot more taxes than I thought I would.

[IsabellaG]

If you earned income as a contractor rather than as an employee, your income would be subject to Self-Employment tax in addition to regular income tax. Self-Employment tax represents Social Security and Medicare taxes.

 The SE tax rate for 2016 is 15.3% of your net profit up to $118,500.