Essential IRS Tax Forms and Deadlines Every Small Business Owner Should Know

Understanding which IRS tax forms your small business must file and when helps you avoid penalties and stay financially organized. Federal forms differ for sole proprietors, limited liability companies (LLCs), and corporation structures. Industry and employees also impact tax obligations.

This guide breaks down the most common tax forms small businesses need to know, including filing requirements and IRS due dates. See which ones apply to your company and get tips for improving your year-round financial planning.

[Read more: 2025 Tax Cliff and Implications for Main Street Businesses: Calculate Your Potential Taxes]

Types of tax forms for businesses

How your business is structured plays a significant role in which IRS tax forms you'll need to file and what information to record year-round. According to the National Federation of Independent Business (NFIB) tax survey, nearly half of small business owners (49%) operate as S corporations. Sole proprietorships, most common among non-employers, make up 22%, while 7% are partnerships, another 7% are LLCs, and 14% are C corporations.

Brought to you by

Simple tax-exempt shopping online & in-store

Walmart Business makes it easy to apply your tax-exempt status when you shop online or in-store with Walmart Pay in the Walmart Business app. Eligible organizations, terms apply.

Learn More

The IRS estimated that business taxpayers, on average, will spend 24 hours preparing taxes for 2024. Record keeping consumes the most time, and knowing which tax forms (and data) you need could help you file on time and save the right tax documents.

The following sections cover the general types of business taxes, including:

• Income tax.
• Estimated tax payments.
• Self-employment tax.
• Employment taxes.
• Excise tax.

[Read more: 15 Tax Deductions Your Business Should Know About]

Income tax forms for sole proprietors, partnerships, and corporations

If you're a sole proprietor, a partner in a partnership, or the owner of an LLC taxed as a sole proprietor or partnership, you'll file your business taxes on your personal return (Form 1040, Individual Income Tax Return, or Form 1040-SR, U.S. Tax Return for Seniors). These types of businesses are flow-through structures, meaning they pass income or loss to individual tax forms.

Here are some IRS guidelines about income tax forms for different types of business structures:

• Sole proprietors file Schedule C, Profit or Loss from Business, with their Form 1040 or Form 1040-SR.
• Partnerships submit an informational return (Form 1065, U.S. Return of Partnership Income). It shows financial details, like total income and deductions, but it doesn't calculate tax.
• Partners get Schedule K-1 forms listing their share of profits or losses reported on Form 1065. They transfer this information to personal returns. Partners may attach Schedule E, Supplemental Income and Loss to Form 1040.
• C corporations file Form 1120, U.S. Corporation Income Tax Return, which is a separate tax return solely for the business.
• S corporations and LLCs taxed as S corporations file Form 1120-S, U.S. Income Tax Return for an S corporation. Like partnerships, S corps pass income and losses to their shareholders. They use Schedule K-1 to report income on personal returns, usually with Schedule E.

IRS forms commonly used by small businesses

Keep track of IRS forms and updates that could affect your liabilities even if you outsource accounting tasks like bookkeeping or tax prep.

A few common business tax forms include:

• Expenses for Business Use of Your Home (Form 8829): Used to calculate home office expenses for Schedule C (Form 1040).
• Depreciation and Amortization (Form 4562): Small businesses use this form when writing off costs of big purchases over time.
• Non-Cash Charitable Contributions (Form 8283): Sole proprietors, partnerships, and corporations can claim non-cash charitable gifts of over $500.
• Application for Automatic Extension of Time To File (Forms 7004 or 4868): Corporations file Form 7004, while flow-through entities file Form 4868 to request filing extensions.
• Credit for Increasing Research Activities (Form 6765): Used to claim the Research and Development Tax Credit, potentially offsetting income tax liabilities.

[Read more: Tariff Impacts on Small Business]

A breakdown of employment tax responsibilities for small business owners

If you hire employees or contractors, it's important to understand which forms you need and file them on time. Any business with employees, regardless of entity type, must file Form 941, Employer's Quarterly Federal Tax Return, or Form 943, Employer's Annual Federal Tax Return for Agricultural Employees, and Form 940, Employer's Annual Federal Unemployment (FUTA) Tax Return. In addition, employers must send W-2s to workers and W-3s to the U.S. Social Security Administration.

Send Form 1099-NEC to freelancers or contractors who were paid $600 or more. If you use third-party payment platforms like PayPal, Venmo, or Stripe, those vendors are responsible for issuing Form 1099-K, not your business. In 2024, the 1099-K threshold was $5,000, but it is $600 for 2025.

[Read more: 10 Legal Requirements for Hiring Employees]

Which businesses must file federal excise tax forms?

According to the IRS, "Excise taxes are taxes that are imposed on various goods, services, and activities." There are over a dozen types of excise taxes, including indoor tanning, fuel sales, and airline tickets. Review the IRS website to view the full list of taxable activities. Report excise taxes on Form 720, Quarterly Federal Excise Tax Return.

Avoiding penalties: A guide to meeting IRS tax deadlines

The IRS charges monthly penalties and daily interest when individuals or businesses miss tax deadlines. Get paperwork and payments in on time by simplifying your system.

Use these tips to build a plan:

• Set up accounting for taxes. Make sure your accounting setup (income and expense categories) transfers smoothly to tax reports.
• Monitor state and local deadlines. Review annual or biennial report requirements to see due dates for business filings.
• Create quarterly checklists. Add tax activities to your quarterly accounting list to streamline estimated income and employment tax payments.
• Prepare for year-end: Follow a fall tax prep checklist to manage all of your quarterly tasks, get ready to close your books, and organize everything for the new year.

Key IRS tax dates for small businesses

Knowing when and how to file your business taxes helps you avoid IRS penalties. Put dates on your calendar with scheduled reminders. Some IRS tax deadlines that fall on a weekend or holiday move to the next business day, so always confirm them at IRS.gov.

Here are the general IRS deadlines:

• January 31: Send 1099-NEC to contractors and W-2s to employees.
• March 15: S corporations must file Form 1120-S or request an extension (Form 7004). For fiscal-year companies, the date falls in the third month after your tax year ends on the 15th day.
• April 15 (or the next business day): Sole proprietors, partners, and LLCs taxed as sole proprietors or partnerships must submit tax returns or Form 4868 extensions. C corps operating on calendar years file Form 1120 or an extension (Form 7004).
• Quarterly estimated tax deadlines: Estimated tax payments are due on or around April, June, September, and January 15.
• Quarterly payroll tax dates: Employers must file Form 941 to report federal income tax withholding and Federal Insurance Contributions Act (FICA) taxes. These are due on the last day of the month following each quarter (April, July, October, and January).

CO— aims to bring you inspiration from leading respected experts. However, before making any business decision, you should consult a professional who can advise you based on your individual situation.

CO—is committed to helping you start, run and grow your small business. Learn more about the benefits of small business membership in the U.S. Chamber of Commerce, here.