Wouldn't adding my 1099 income and my W-2 income be subject to double taxation?

[jmario-ranval]

I get taxed at 15.3% for 92.35% of my self employment income. I do understand where this taxation comes from. However, would I be getting doubled taxed when I add this income to my W-2 income to calculate how much taxes I have to pay for that? I feel like it is indirectly double taxing my 1099 income. First by taxing it directly with 15% and then indirectly after adding it with my w-2 income to give me a much higher income which would place me at a higher bracket with higher taxes. Is this how it works? Or can I have my w-2 taxed independently and then my 1099 taxed independently and then add both together to give a final amount owed?

[VolvoGirl]

No.  It's ok and all works out.  You owe the self employment tax in addition to the regular income tax on all your income.

But, If you also have W2 income, you have to break out the Social Security and Medicare taxes. Only the Social Security part maxes out.  Turbo Tax does it automatically for you.

The SE tax includes what you already paid in from your W2s so your schedule SE tax will only be the difference up to the max amount of $7,960.80 for social security. The max income for social security for 2018 is $128,400 between W2 wages and the schedule C Net Profit.

Medicare is 2.9% (both er & ee parts) of all wages & schedule C profit - no max.