You pay BOTH sides of the Social Security tax so that is 12.4% right off the top, no deductions or exemptions. ($12,400) Leaving you $87,600 Then you are in the 24% tax bracket assuming you can not deduct anything so you pay that on the $87,600 ($21,024). That leaves you with $66,576. You can greatly reduce your tax burden by incorporating your business then pay yourself a dividend. Of course, this is in the USA, I bet in the UK your taxes will be a lot higher.