Want a business address to use for tax filings? With Stable, we'll set you up with a permanent business address that you can use on your federal and state tax returns, registration documents, banks, and more.
Tax season is a time that needs to be on every company’s radar. Filing your annual federal tax return or corporate income tax is extremely important with the IRS, especially if you’d like to remain in good standing and avoid any late penalties. But when exactly is the next deadline to file taxes for business?
Depending on your specific business entity structure (i.e LLCs, corporations, partnerships, multi-member LLCS, Sole proprietors, etc), the 2026 tax due dates may vary.
Below, we share a list of the standard upcoming federal business tax deadlines and the forms that may be due based on your business entity type:
C corporation deadlines and tax forms (C-corp)
The IRS tax return deadline for C corporations, also known as C-corp, is due on April 15, 2026.
Forms include the U.S Corporation Income Tax Return known as Form 1120.
This tax form needs to be submitted to the International Revenue Service (IRS) so that C corporations can understand their tax liability and find out how much business tax they owe.
Additional Links for C corporation
• Form 1120 Instructions, the U.S. Corporation Income Tax Return
S corporation deadlines and tax forms (S-corp)
The IRS tax return deadline for S corporations, also known as S-corp, is due on March 15, 2026.
Forms include the U.S Income Tax Return for S Corporations known as the Form 1120S and Schedule K-1.
These tax forms need to be submitted to the International Revenue Service (IRS) so that S Corporations can understand their tax liability, find out how much business tax they owe, and report each party’s share of the corporation's income, deductions, credits, etc.
Additional Links for S corporation
• What is a K-1 Schedule Tax form?
• About Schedule K-1 (Form 1120-S), Shareholder’s Share of Income, Deductions, Credits, etc.
• Form 1120-S Instructions , the U.S. Income Tax Return for an S Corporations
Partnerships and multi-member LLCs deadlines and tax forms
The IRS tax return deadline for partnerships and multi-member LLCs is due on March 15, 2026.
Forms include a U.S Return of Partnership Income known as the Form 1065 and Schedule K-1.
These tax forms need to be submitted to the International Revenue Service (IRS) so that Partnerships and multi-member LLCs can understand their tax liability, find out how much business tax they owe, and report the tax amount that is being passed to each partner.
Additional Links for partnerships and multi-member LLCs
• What is a K-1 Schedule (1065) Tax form?
• About Schedule K-1 (Form 1065), Partner's Share of Income, Deductions, Credits, etc
• Form 1065 Instructions, the U.S. Return of Partnership Income
Sole proprietorships and single-member LLCs deadlines and tax forms
The IRS tax return deadline for sole proprietorships and single-member LLCs is due on April 15, 2026.
Forms include the U.S Individual Income Tax Return known as Form 1040 and a Profit or Loss from Business known as a Schedule C (Profit or Loss from Business).
These tax forms need to be submitted to the International Revenue Service (IRS) so that sole proprietors and single-member LLCs can understand their tax liability, find out how much business tax they owe, and report the income or loss of their business.
Additional Links for sole proprietorships and single-member LLCs
• About Schedule C, Profit of Loss from Business (Sole Proprietorship)
• Form 1040 Instructions, the U.S. Individual Income Tax Return
Note: Business tax deadlines are still subject to change. These dates usually remain the same every year, however they can sometimes be extended due to special circumstances — For example, the 2021 business tax deadline was extended for sole proprietors and single-owner LLCs due to the Covid-19 virus.
Tax filing extensions
Business filing extensions are available if you’d like to extend your tax filing deadline by an additional six months.
- For corporations, partnerships, and LLCs taxed as partnerships or corporations, file Form 7004
- For sole proprietors and single-member LLCs, file Form 4868
The deadline to submit these forms is the same as the original federal tax deadline for your business. It’s important to note that any extension granted is for filing only, not for payments due. Estimated taxes must still be paid by the original deadline.
More information on business tax extensions can be found on the IRS website.
2026 business tax deadlines
Understanding when business deadlines to file taxes in 2026 is essential for staying compliant, avoiding penalties, and keeping your company in good standing with the IRS and state agencies. Whether you’re running a C corporation, S corporation, partnership, LLC, or sole proprietorship, tax deadlines vary based on your entity type — and missing a filing date can quickly lead to unnecessary fines or administrative headaches.
As your business grows, having accurate, up-to-date records and a reliable business address for receiving tax notices and official correspondence becomes just as important as meeting the deadlines themselves. Stable helps businesses stay organized by providing a permanent, real street address and secure access to important mail, so nothing critical gets lost, delayed, or overlooked during tax season. Get started here.
