Your LLC’s tax return due date depends on how the IRS classifies the business. Single-member LLCs treated as disregarded entities and LLCs that have elected C-corporation status file by April 15. Multi-member LLCs taxed as partnerships and LLCs that have elected S-corporation status file by March 15. All four dates assume a calendar tax year and shift to the next business day when they fall on a weekend or federal holiday.1Internal Revenue Service. When to File
The IRS has no separate tax category for LLCs. It assigns a default classification based on the number of owners, and the LLC can elect a different one.2Internal Revenue Service. Limited Liability Company (LLC) That classification decides which form you file and when.
Single-Member LLC: April 15
If you are the only owner and have not elected corporate treatment, the IRS treats your LLC as a disregarded entity.3Internal Revenue Service. Single Member Limited Liability Companies The business does not file its own return. You report the income and expenses on Schedule C (or Schedule E for rental income, or Schedule F for farming) attached to your Form 1040, and your deadline is the individual due date: April 15 for calendar-year filers.
Multi-Member LLC Taxed as a Partnership: March 15
An LLC with two or more owners that has not elected corporate status is taxed as a partnership by default.4Internal Revenue Service. LLC Filing as a Corporation or Partnership The LLC files Form 1065, an informational return, by March 15 for a calendar year.5Office of the Law Revision Counsel. 26 USC 6072 – Time for Filing Income Tax Returns The partnership itself owes no income tax.
Along with Form 1065, the partnership issues each member a Schedule K-1 showing that member’s share of profits, losses, deductions, and credits.4Internal Revenue Service. LLC Filing as a Corporation or Partnership Members carry those amounts to their personal returns. The March 15 date sits a month ahead of April 15 so members have their K-1s in hand before their individual returns are due.
LLC Taxed as an S-Corporation: March 15
An LLC that has elected S-corporation status files Form 1120-S by the same March 15 calendar-year deadline as a partnership.5Office of the Law Revision Counsel. 26 USC 6072 – Time for Filing Income Tax Returns Like a partnership, the S-corporation is a pass-through entity: it reports income and issues Schedule K-1s to shareholders, who include those amounts on their personal returns.6Internal Revenue Service. S Corporations
LLC Taxed as a C-Corporation: April 15
An LLC that has elected C-corporation classification files Form 1120 and pays tax at the entity level.4Internal Revenue Service. LLC Filing as a Corporation or Partnership The return is due on the 15th day of the fourth month after the tax year ends, which is April 15 for a calendar year.5Office of the Law Revision Counsel. 26 USC 6072 – Time for Filing Income Tax Returns
Fiscal Year Filers
If your LLC uses a fiscal year (any 12-month period that ends on a date other than December 31), the deadline is measured from the last day of that year.
- Partnerships and S-corporations file on the 15th day of the third month after the fiscal year ends. A fiscal year ending June 30 produces a September 15 deadline.5Office of the Law Revision Counsel. 26 USC 6072 – Time for Filing Income Tax Returns
- C-corporations file on the 15th day of the fourth month after the fiscal year ends. A fiscal year ending June 30 produces an October 15 deadline.7Internal Revenue Service. Publication 509 (2026), Tax Calendars
How to Get an Extension
You can request an automatic six-month extension, but the request must reach the IRS by the original filing deadline.
- Single-member LLC owners file Form 4868, which extends the personal return to October 15.8Internal Revenue Service. Get an Extension to File Your Tax Return
- Partnerships, S-corporations, and C-corporations file Form 7004. A March 15 deadline extends to September 15; an April 15 deadline extends to October 15.9Internal Revenue Service. Instructions for Form 7004
Extension forms can be filed electronically or on paper, and e-filers usually receive confirmation within 24 hours.10Taxpayer Advocate Service. Options for Filing a Tax Return The IRS grants the extension automatically if the form is complete, arrives on time, and includes a reasonable estimate of your tax liability.9Internal Revenue Service. Instructions for Form 7004
An extension buys time to file, not time to pay. Any tax owed is still due by the original deadline, and unpaid balances accrue penalties and interest even when the extension is valid.8Internal Revenue Service. Get an Extension to File Your Tax Return
Penalties for Missing the Deadline
The IRS charges separate penalties for filing late and paying late, and they can apply to the same return.
Failure to File
For an LLC that owes tax (a single-member LLC’s owner or a C-corporation LLC), the penalty is 5 percent of the unpaid tax for each month or partial month the return is late, capped at 25 percent.11Internal Revenue Service. Failure to File Penalty A return more than 60 days late faces a minimum penalty equal to the lesser of $525 or the full amount of tax owed.12Internal Revenue Service. Topic No. 653, IRS Notices and Bills, Penalties and Interest Charges
Failure to Pay
Unpaid tax triggers a separate 0.5 percent monthly penalty on the outstanding balance, also capped at 25 percent.12Internal Revenue Service. Topic No. 653, IRS Notices and Bills, Penalties and Interest Charges When both penalties apply in the same month, the failure-to-file penalty is reduced by the failure-to-pay amount. Interest also runs on unpaid balances at a rate that adjusts quarterly; the rate for the first quarter of 2026 is 7 percent.13Internal Revenue Service. Quarterly Interest Rates
Late Partnership and S-Corporation Returns
Because these entities do not owe tax themselves, the penalty is not tied to a balance. For returns due in 2026, the IRS charges $255 per partner or shareholder for each month or partial month the return is late, up to 12 months.11Internal Revenue Service. Failure to File Penalty A four-member LLC that files Form 1065 three months late owes $3,060 in penalties on a return that carries no tax of its own.
Quarterly Estimated Tax Payments
The annual return is not the only date to watch. If you expect to owe $1,000 or more in federal income and self-employment taxes for the year, you must make quarterly estimated payments.14Internal Revenue Service. Estimated Taxes This covers single-member LLC owners, partners in a multi-member LLC, and S-corporation shareholders who receive income without withholding. LLCs taxed as C-corporations have a separate corporate estimated tax rule that kicks in at $500 of expected tax.
For 2026 calendar-year filers, the quarterly due dates are:
- 1st quarter: April 15, 2026
- 2nd quarter: June 15, 2026
- 3rd quarter: September 15, 2026
- 4th quarter: January 15, 2027
You can skip the January 15, 2027 payment if you file your 2026 return and pay any remaining balance by February 1, 2027.15Internal Revenue Service. Form 1040-ES, Estimated Tax for Individuals Individuals use Form 1040-ES; C-corporation LLCs use Form 1120-W.
State Deadlines Are Separate
Federal dates are only part of the picture. Most states require LLCs to file an annual or biennial report and pay a fee to stay in good standing, and those deadlines and fees are set independently. Missing a state filing can bring late penalties, loss of liability protection, or administrative dissolution. Some states also impose their own income tax, franchise tax, or gross receipts tax on LLCs, and while states that conform to federal classification generally follow the same pass-through or corporate structure you elected, they set their own forms and due dates. Check with your state’s secretary of state office for the specifics.