If I filed my taxes already can I still do my taxes for my business

[rjs]

The tax return that you filed should have included your business income. You have to include all your income in one tax return. After the IRS has processed the tax return that you filed, you will have to file an amended return (Form 1040-X) to add your business income.

Your business might or might not have to also file its own tax return, depending on the business structure. If it's a sole proprietorship there is no separate business tax return. You just include it on Schedule C in your personal tax return. If the business is a partnership, S-corp, or C-corp, the business has to file its own tax return. A partnership or S-corp has to give you a Schedule K-1 with the income information that you have to include in your personal tax return.

It might be a good idea for you to consult a local tax professional who can show you how to properly  handle the taxes for your business.

[Critter-3]

If your business is a C-Corp, S-Corp or partnership then your return is late ... calendar company returns were due 3/15/21 unless you put them on extension and the penalties are piling up monthly.  Seek local professional assistance if this is your situation and you are not well versed in how to file an 1120. 1120-S or 1065. 

[Mike9241]

if your business income is from self-employment it was supposed to be included on Schedule C with your 1040.  you not only owe income taxes on this income but also self-employment taxes. as others have said seek out a pro. depending on the amount of additional taxes involved, you could be billed for substantial penalties and interest for paying late and not reporting the income with your return. also, for the 2021 tax year, you may need to pay estimated taxes. payments were due in May and June so you face underpayment of estimated tax penalties when you file that return. estimated tax payments would also be due 9/15/21 and 1/15/2022