MO MO-1120S Information
Every S corporation must file Form MO-1120S if they file Federal Form 1120S and the S corporation has: 1) a shareholder that is a Missouri resident; or 2) any income derived from Missouri sources (Section 143.471, RSMo). Attach a copy of Federal Form 1120S and all Schedule K-1(s). Qualified subchapter S subsidiaries (QSSS) must file a separate Form MO-1120S and attach its separate balance sheet if they are engaged in business in Missouri. The QSSS must also check Box D on Form MO-1120S
Link to official form info: Missouri MO-1120S
Link to official form info for MO-1120S
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- Monday Mar 16, 2026
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12 Missouri Tax Filings & Forms:
MO-1040 - Individual Income Tax Return-Long Form MO-NRI - Missouri Income Percentage MO-1040A - Individual Income Tax Return Single/Married (One Income) MO-1120 - Corporation Income Tax Return MO-1120S/MO-FT - Corporation Franchise Tax Schedule MO-1120S - S Corporation Income Tax MO-1065 - Partnership Return of Income MODES-4-7 - Contribution and Wage Report MO941-P - Employer's Return of Income Taxes Withheld MO W3 - Transmittal of Tax Statements 53-1 - Sales Tax ReturnAre we missing a Missouri tax form?
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