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IRS Form 1065 Due Dates 2026 – Partnerships, multi-member LLCs taxed as partnerships, and certain other entities must file IRS Form 1065 (U.S. Return of Partnership Income) to report income, deductions, gains, losses, credits, and other items. The form itself does not trigger tax payment—the income passes through to partners via Schedule K-1—but missing the deadline carries stiff penalties.
This guide, based on official IRS sources including the 2025 Instructions for Form 1065, Publication 509 (2026) Tax Calendars, and IRS tax calendars (as of February 2026), explains exact due dates, extension rules, e-filing requirements, and penalties for the 2025 tax year returns filed in 2026.
What is IRS Form 1065 and Who Must File It?
Form 1065 is an information return filed by:
- Domestic partnerships
- Foreign partnerships with U.S. trade or business income or U.S.-source income
- LLCs classified as partnerships for federal tax purposes
Exceptions: Partnerships with no income and no deductible expenditures, or certain electing-out entities under IRC Section 761(a). Most active partnerships must file even with zero profit or loss.
Partners receive Schedule K-1 (Form 1065) (and Schedule K-3 for foreign partners or international tax items) to report their share on personal returns.
Standard IRS Form 1065 Due Dates
The general rule: Form 1065 is due on the 15th day of the 3rd month after the end of the partnership’s tax year.
Calendar-Year Partnerships (Most Common)
- Tax year ends December 31, 2025
- Original due date: March 16, 2026 (Monday)
Why March 16 instead of March 15? March 15, 2026, falls on a Sunday. Per IRS rules, if the due date lands on a Saturday, Sunday, or legal holiday in the District of Columbia or the filing state, the deadline shifts to the next business day.
The same deadline applies to furnishing Schedules K-1 and K-3 to each partner.
Fiscal-Year Partnerships
Use the 15th day of the 3rd month after your tax year ends. Examples (2025–2026 fiscal periods):
| Tax Year End Date | Original Due Date (2026) |
|---|---|
| January 31, 2026 | April 15, 2026 |
| February 28, 2026 | May 15, 2026 |
| March 31, 2026 | June 15, 2026 |
| June 30, 2026 | September 15, 2026 |
| September 30, 2026 | December 15, 2026 |
| October 31, 2026 | January 15, 2027 |
Adjust for weekends/holidays in the filing state or D.C.
Short tax years or final returns: File by the regular due date for the short period shown at the top of Form 1065.
How to Get an Automatic Extension?
Partnerships receive an automatic 6-month extension by filing Form 7004 (Application for Automatic Extension of Time To File Certain Business Income Tax, Information, and Other Returns) by the original due date. No reason required.
Extended Due Dates for 2025 Returns
- Calendar-year partnerships → September 15, 2026
- Fiscal-year examples shift 6 months forward (adjust for holidays)
Important notes:
- File Form 7004 electronically or by mail/fax.
- The extension applies only to filing the return—not to furnishing K-1s/K-3s to partners (still due by original deadline) or paying any related taxes.
- Partners may need to file their own extensions (Form 4868) separately.
E-Filing Requirements for Form 1065 (Updated for 2025+)
Since tax year 2024, most partnerships must e-file:
- If the partnership files 10 or more returns of any type (information, income, employment, or excise) during the tax year, or
- If the partnership has more than 100 partners
Exceptions/Waivers:
- Hardship waiver (written request to Ogden Submission Processing Center)
- Religious exemption (note “Religious Exemption” on paper Form 1065)
- Bankruptcy returns or pre-computed penalty/interest returns
E-filing uses the Modernized e-File (MeF) system. Software providers or tax professionals handle this for most filers.
Penalties for Missing IRS Form 1065 Due Dates
The IRS imposes significant penalties for late or incomplete filings:
| Violation | Penalty Amount (2025 Tax Year) | Maximum/Details |
|---|---|---|
| Late filing of Form 1065 | $255 per month or part of a month × number of partners | Up to 12 months |
| Failure to furnish correct K-1/K-3 to partners | $340 per schedule | Per partner/schedule; higher for intentional disregard |
| Incomplete or inaccurate return | Same as late filing | Reasonable cause may waive |
Example: A 10-partner partnership filing 1 month late faces $2,550. After 12 months: up to $30,600.
Penalties can be abated for reasonable cause (e.g., documented reliance on a tax professional, natural disaster). File the return as soon as possible and attach an explanation if contacted by the IRS.
Tips to Avoid Missing the Deadline
- Mark your calendar now: March 16, 2026, for most partnerships.
- Gather all partner information early—K-1s must go out by the same date.
- Use IRS-approved tax software or a qualified CPA for e-filing.
- File Form 7004 early if you need more time.
- Check IRS.gov/TaxCalendar or Publication 509 for updates.
- Use IRS-designated private delivery services for proof of timely mailing (if paper filing is allowed).
Frequently Asked Questions (FAQ)
What is the Form 1065 due date for 2025 calendar-year partnerships?
March 16, 2026 (original); September 15, 2026 (with extension).
Do I need to file Form 1065 if the partnership had no income?
Generally yes, unless there were also no deductible expenditures or credits. Check the instructions.
Can partners get their K-1s later than the partnership due date?
No—K-1s must be furnished by the same deadline as the Form 1065 filing.
Is there a penalty for filing Form 1065 late even if no tax is owed?
Yes—the $255-per-partner-per-month penalty still applies because it is an information return.
Where can I find the official 2025 Form 1065 and instructions?
Download from IRS.gov: About Form 1065 and 2025 Instructions for Form 1065 (PDF).
Final Reminder
The IRS Form 1065 due date for most partnerships in 2026 is March 16. Don’t wait until the last minute—start gathering records and consulting your tax advisor today.
For the most current information, always refer directly to IRS.gov or consult a tax professional, as rules can change and individual circumstances vary.
Sources (all accessed February 2026):
- 2025 Instructions for Form 1065 (IRS)
- Publication 509 (2026), Tax Calendars (IRS)
- IRS First Quarter Tax Calendar 2026
- About Form 1065 page (IRS.gov)
Stay compliant and avoid unnecessary penalties—file on time!