Business Tax Preparation and Taxpayer Filing Requirements
Return Types and Due Dates
Match the entity to the return and the deadline. Partnerships file Form 1065, S corporations Form 1120-S, and C corporations Form 1120. Calendar-year partnership and S corporation returns are due March 15; calendar-year C corporation returns are due April 15. Extensions are filed on Form 7004 and extend the filing date, not the payment date. The recurring trap is confusing the extended due date with an extension of time to pay, or applying the individual April 15 date to a pass-through entity.
Information Reporting and Schedules K-1
Pass-through entities issue Schedule K-1 to report each owner's distributive share of income, deductions, credits, and separately stated items. Candidates must know which items are separately stated (capital gains, charitable contributions, investment interest, tax-exempt income) versus aggregated in ordinary business income. A frequent question tests that separately stated items retain their character in the owner's hands.
Employment and Information Returns
Understand Forms W-2 and 1099-NEC reporting for worker classification, and the requirement to reconcile wage reporting on the entity return. Payroll tax deposits, Form 941, and backup withholding appear as supporting details.
Worked Example
A calendar-year partnership with a two-month extension has a filing deadline of September 15. Its return is timely filed August 1 but the tax due was unpaid until August 1. The extension does not relieve the failure-to-pay penalty accruing from the original March 15 date.