Schedule K-1 is due to you by March 15 if it comes from a partnership or S corporation on a calendar year, and by April 15 if it comes from a trust or estate. Those are the same days the entity’s own return (Form 1065, 1120-S, or 1041) is due, so any extension the entity takes pushes your K-1 out by the same amount of time. That answers when K-1s are due in the ordinary case; the wrinkles come from fiscal years, extensions, and late deliveries.
The Two Baseline Deadlines
A partnership filing Form 1065 or an S corporation filing Form 1120-S must furnish each partner or shareholder a Schedule K-1 by the 15th day of the third month after the entity’s tax year ends.1Internal Revenue Service. Publication 509 (2026), Tax Calendars For a December 31 year-end, that lands on March 15.
Trusts and estates get an extra month. A fiduciary filing Form 1041 must deliver Schedule K-1 to each beneficiary by the 15th day of the fourth month after the tax year ends.2Internal Revenue Service. Instructions for Form 1041 and Schedules K-1 For calendar-year filers that is April 15, the same day your own Form 1040 is due.3Internal Revenue Service. 2Internal Revenue Service. Instructions for Form 1041 and Schedules K-1
How an Entity Extension Moves the K-1 Deadline
An entity that needs more time files Form 7004 for an automatic extension.4Internal Revenue Service. About Form 7004, Application for Automatic Extension of Time to File Certain Business Income Tax, Information, and Other Returns The length depends on the entity type:
- Partnerships and S corporations get six months. For calendar-year filers, that moves the K-1 deadline from March 15 to September 15.
- Trusts and estates get five and a half months. For calendar-year filers, that moves the K-1 deadline from April 15 to September 30.5Internal Revenue Service. Instructions for Form 7004
Because the K-1 delivery deadline is tied to the entity’s return, one Form 7004 covers both. The entity does not file anything additional to delay furnishing your schedule.
Your Personal Return Doesn’t Extend Automatically
An entity’s extension does not give you extra time to file your Form 1040. If a partnership pushes to September 15 and your K-1 hasn’t arrived, you still need to file your own extension using Form 4868 before April 15. Form 4868 gives you an automatic six months, until October 15, to file.6Internal Revenue Service. Form 4868, Application for Automatic Extension of Time to File U.S. Individual Income Tax Return
The extension covers filing, not payment. You still need to estimate your tax and pay by April 15 to avoid interest and late-payment penalties.
What to Do If Your K-1 Is Late
Late K-1s are common with pass-through entities, and you have a few workable options.
Extend Your Own Return
If you expect the K-1 before October 15, file Form 4868, pay what you reasonably estimate you owe, and finish the return once the schedule shows up.
File Using Estimated Figures
If the entity still hasn’t filed or delivered the K-1 by the time you need to file, even after your own extension, you can file using estimated numbers. Attach Form 8082 to report your best estimate of the income, deductions, and credits from the entity. Note on the form that no K-1 was received, enter zero in the column for the entity’s reported amount, and enter your estimate in the column for the amount you believe is correct.7Internal Revenue Service. Instructions for Form 8082 If the K-1 later shows different numbers, you’ll amend.
Protect Yourself From Estimated Tax Penalties
Pass-through income counts toward your quarterly estimated tax obligations even before the K-1 that reports it exists. The IRS expects you to include your share of pass-through income when calculating estimates during the year.8Internal Revenue Service. 20.1.3 Estimated Tax Penalties When you don’t have current-year data, the prior-year safe harbor is the simplest shield: pay in at least 100 percent of the tax shown on last year’s return (110 percent if your adjusted gross income was over $150,000) through withholding and estimates, and you generally avoid an underpayment penalty regardless of how the current year turns out.9Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty
If a Corrected K-1 Arrives After You File
Sometimes the entity finds an error after you’ve already filed. What you do next depends on the type of entity.
Most Partnerships
Partnerships under the centralized partnership audit regime (most partnerships with tax years beginning after 2017) do not issue corrected K-1s. The partnership files an administrative adjustment request with the IRS, and if the change affects you, the partnership sends you Form 8986 rather than an amended K-1.10Internal Revenue Service. File an Administrative Adjustment Request for a BBA Partnership You report the effect on Form 8978 with your return for the year the partnership furnished Form 8986, not by amending the earlier year.
S Corporations, Trusts, and Estates
When one of these entities issues a corrected K-1, you generally file an amended individual return on Form 1040-X to reflect the new figures.11Internal Revenue Service. Topic No. 308, Amended Returns Form 1040-X can be filed electronically, and refunds can go by direct deposit. Processing usually takes 8 to 12 weeks and can stretch to 16. The IRS “Where’s My Amended Return?” tool shows status starting about three weeks after filing.
Electronic Delivery Doesn’t Change the Date
An entity can deliver your K-1 electronically, but only with your affirmative consent, and it must give you a clear disclosure about how to access and print the document before or when you consent.12Internal Revenue Service. Revenue Procedure 2012-17 You can withdraw consent at any time before the K-1 is furnished, in which case the entity must send paper. Whether your K-1 arrives by mail or through a portal, the March 15, April 15, or extended deadline is the same.