Domestic corporations use this form to: Report their income, gains, losses, deductions, credits. Figure their income tax liability.Get a list of IRS forms for corporations. If you have multiple s corporations you're going to need to fill out multiple 7004s or Partnerships so just be aware of that the 4868 will cover all of that. If you are a C corporation, use the information in the chart below to help you determine some of the forms you may be required to file. Form 990 is an information return that most organizations claiming federal tax-exempt status must file yearly with the IRS. IRS form 2553 can allow an SMLLC to reap the tax benefits of an S-Corp. Read more from the experienced attorneys at BK Law. There are many ways to get in trouble with the IRS.