text: what is the tax liability of a 1099-ed contractor?   you must pay self employment tax on the non employee compensation.....this is equal to 15.3% ...12.4% for social security and 2.9% for medicare and then you pay regular income tax on your adjusted gross income minus the deductions.....now remember that if you are getting a 1099misc and you are earning this money as a business (yes there is a difference because bonuses come on a 1099 but are not subject to ss and mci every instance) you can count your deductions from whatever the amount of the 1099 is including mileage which just went up again this year