S-Corp tax filing doesn’t have to be stressful
Use this checklist to organize shareholder details, income, deductions, Schedule K-1s, and required documents before you file.
The deadline to file your S corporation return or request an
extension is MARCH 15, 2027
Section 01
Basic Information
Verify Your Business Filing Type
Ensure your S corporation is properly registered with the IRS for Form 1120-S filing. Not sure? Call the IRS Business Help Line: 1-800-829-4933
Employer Identification Number (EIN)
Have your EIN handy. If you need a new one, apply online at IRS.gov
State Reporting Details
Gather state and local ID numbers for every location where your business has a tax obligation/nexus
Organizational Documents
Gather state and local ID numbers for every location where your business has a tax obligation/nexus
Previous Tax Returns
Locate your prior year’s Form 1120-S and shareholder Schedule K-1s for reference while completing Form 1120-S
Estimated Tax Payments
List all S corporation federal, state, and local taxes paid during the year, including dates and amounts
Shareholder Details
Collect names, addresses, and SSNs or EINs for all partners active during the tax year
Ownership & Profit Details
List each shareholder’s ownership percentage and allocation of income or loss for accurate Form 1120-S filing
Financial Activity Reports
Financial activity reports including addresses, compensation, or benefit procedures and tax items
Ownership Changes
Document shareholder ownership changes, including issue, transfer, or redemption dates, for Form 1120-S filing
Section 03
Documents Received
Quarterly Tax Forms
Gather all received forms such as 1099-INT, 1099-MISC, 1099-DIV, 1099-R, and 1099-NEC
Ownership & Profit Details
List all shareholder distributions and each shareholder’s allocation of income or loss for accurate Form 1120-S filing
Schedule K-1
Review shareholder Schedule K-1 forms for reported business income, deductions, and credits
Credit Certificates
Collect any credit certificates issued by federal or state agencies
Section 04
Business and Financial Records
Accounting Records
Run a P&L report/balance sheet from your accounting software (QuickBooks Online)
Bank and Credit Card Statements
Review statements to validate business expenses and interest payments for Form 1120-S
Payroll Reports
Copies of issued Forms W-2 and W-3, including 940 and 941/944 returns, plus copies of prior and current payroll taxes paid
Multi-State Activity
For partners in multiple states, compile reports showing sales, payroll, and property values to state
Business Registrations
Record the cost of goods/materials bought for resale or production and the year-end value of inventory
Section 05
Asset Records
Depreciation Schedules
List asset details such as cost, purchase date, prior depreciation, and bonus/section 179 percentage
Log Purchases
Log purchases made during the year, including costs and dates of service
Disposed Assets
Detail sales proceeds, trade-in values, expenses of sale, and accumulated depreciation for assets sold or traded
Vehicle Mileage Log
Provide a mileage log for any business-owned or employee-use vehicles, including parking/tolls/insurance and total mileage
Download Your 1120-S S Corporation Checklist Now!
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