Key Tax Deadlines for LLC Owners

6 min read Updated Jan 15, 2025

Missing tax deadlines costs money in penalties and interest. Here's a complete guide to the tax dates every LLC owner needs to know.

Annual Tax Return Deadlines

Your annual return deadline depends on how your LLC is taxed:

LLC Type Form Deadline
Single-member LLC Schedule C (with Form 1040) April 15
Multi-member LLC (Partnership) Form 1065 March 15
LLC taxed as S-Corp Form 1120-S March 15
LLC taxed as C-Corp Form 1120 April 15
Note

Partnership and S-corp returns are due March 15 (one month before personal returns) so members have their K-1s in time to file their personal returns by April 15.

Quarterly Estimated Tax Payments

LLC owners typically need to make quarterly estimated tax payments because no taxes are withheld from their income. You'll owe estimates if you expect to owe $1,000 or more in taxes.

Due Dates

  • Q1: April 15
  • Q2: June 15
  • Q3: September 15
  • Q4: January 15 (of the following year)

If the due date falls on a weekend or holiday, the deadline moves to the next business day.

How to Calculate

Two safe harbor methods to avoid underpayment penalties:

  1. 100% of last year's tax: Pay at least 100% of what you owed last year (110% if AGI was over $150,000)
  2. 90% of current year's tax: Pay at least 90% of what you'll owe this year
Tip

If your income is uneven, use the annualized income installment method to potentially reduce quarterly payments during low-income periods.

Filing Extensions

You can request an automatic extension to file your return:

  • Form 1040 (personal): 6-month extension to October 15
  • Form 1065 (partnership): 6-month extension to September 15
  • Form 1120-S (S-corp): 6-month extension to September 15
Warning

Extension to file is NOT an extension to pay. You still owe estimated taxes by the original deadline. Only the paperwork filing is extended.

Penalties for Missing Deadlines

Late Filing Penalty

5% of unpaid taxes for each month (or part of month) the return is late, up to 25% maximum.

Late Payment Penalty

0.5% of unpaid taxes for each month (or part of month), up to 25% maximum.

Underpayment of Estimated Taxes

The IRS charges interest on the underpaid amount for each quarter. Rates change quarterly based on federal short-term rates.

Partnership/S-Corp Late Filing

$220 per shareholder/partner per month, up to 12 months. A 4-member LLC filing 3 months late could face $2,640 in penalties.

Complete LLC Tax Calendar

Date Deadline
January 15 Q4 estimated taxes due
January 31 W-2s and 1099s due to recipients
March 15 Partnership (Form 1065) and S-Corp (Form 1120-S) returns due
April 15 Personal returns, C-Corp returns, Q1 estimates due
June 15 Q2 estimated taxes due
September 15 Q3 estimates due; extended partnership/S-Corp returns due
October 15 Extended personal and C-Corp returns due
Tip

Set calendar reminders at least 2 weeks before each deadline. This gives you time to gather documents and avoid the stress of last-minute filing.

Frequently Asked Questions

Frequently Asked Questions

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