The 8,477 additional taxes is the Self Employment tax. You owe that in addition to the regular income tax on all your income including the Net Profit on your business income. You should consider the W2 income. The W2 withholding might not be enough to cover the regular tax on all your income. It's all combined on your tax return.
You pay Self Employment tax on $400 or more of net profit from self-employment in addition to any regular income tax. You pay 15.3% SE tax on 92.35% of your Net Profit greater than $400. The 15.3% self employed SE Tax is to pay both the employer part and employee part of Social Security and Medicare. So you get social security credit for it when you retire.
You must make quarterly estimated tax payments for the current tax year if both of the following apply:
- 1. You expect to owe at least $1,000 in tax for the current tax year, after subtracting your withholding and credits.
- 2. You expect your withholding and credits to be less than the smaller of:
90% of the tax to be shown on your current year’s tax return, or
100% of the tax shown on your prior year’s tax return. (Your prior year tax return must cover all 12 months.)
Here are the blank Estimates and instructions…..
https://www.irs.gov/pub/irs-pdf/f1040es.pdf
Or you can pay on the IRS website. Be sure to pick 2023 1040ES payment
https://www.irs.gov/payments
