Does the IRS/SS send me a bill for the 15.3% self employment tax? How/where do I pay that amount when filing my taxes?

Hi Gerhard!

You may make quarterly estimated tax payments toward your potential tax liability throughout the year, if you estimate to owe more than $1000 in taxes, you can find more info on that here.

If you don’t make any estimated tax payments through out the year or underpay through out the year and still have a tax balance due when you file your annual taxes, you will be notified of that amount upon filing. That amount includes the amount due for self-employment tax, state and federal income tax.