Key takeaways
- Tax year 2026 Form 1065 is due March 15, 2027, and a Form 7004 extension gives six more months to file, not to pay.
- Tax year 2026 K-1 statements furnished in 2027 cost $60, $130 or $340 each, depending on when they are corrected.
- A late tax year 2026 Form 1065 costs $260 per partner per month, for up to 12 months.
- A foreign partner adds Form 8804, Form 8805 and Form 8813 work, and the Form 8805 copy is due on the extended date.
- If the K-1 is not final by early April, send the dependent partner a written estimate and a Form 4868 recommendation before April 15.
What the K-1 reports and what it does not
Form 1065 is the partnership's information return. Each Schedule K-1 reports one partner's share of income, deductions and credits, plus the capital, liability and other items in Items J through L.
The K-1 is not a basis statement. The partner instructions say Item L cannot be used to figure adjusted basis, so a partner who needs basis also needs the partnership's basis records.
The loss a partner may claim can be less than the K-1 shows. The partner completes Form 6198 for the at-risk rules and uses Form 8582 for passive losses.
Deadlines for the 2026 return and the partners' Forms 1040
Form 1065 for a calendar-year partnership is due March 15 under 26 U.S.C. 6072(b), so for tax year 2026 it is March 15, 2027. If that date falls on a weekend or legal holiday, 26 U.S.C. 7503 moves it to the next business day.
A Form 7004 extension gives an automatic period the IRS describes as generally 6 months. It does not extend the time to pay.
Partners run on their own dates. The IRS says the individual due date is generally April 15, so a tax year 2026 Form 1040 is due April 15, 2027. Form 4868 gives until October 15, 2027 to file, but tax owed is still due April 15, 2027.
When the partnership must furnish the K-1
Under 26 U.S.C. 6031(b), the partnership must furnish each partner a copy on or before the day the return is required to be filed. For tax year 2026, plan on March 15, 2027.
The statute does not say whether an approved Form 7004 extension moves that day for domestic partners. Unless the partnership confirms an extended date in writing, use March 15, 2027.
Foreign partners have a clearer rule. The Form 8804 instructions say Form 8805 must reach each foreign partner by the partnership return's due date, including extensions.
Foreign partners: Form 8804, Form 8805 and section 1446
A partnership with a foreign partner also files Form 8804 on or before March 15 for a calendar-year partnership, and pays section 1446 tax with Form 8813. Form 8813 must accompany each payment.
The section 1446 rate is generally 37% for a noncorporate foreign partner and 21% for a corporate partner. Confirm each partner's status from its documentation, not from its address.
Decision rule: if any partner is foreign, the Form 8805 amounts, Form 8813 payments and K-1 amounts must agree before anything goes out.
What to collect from each partner
Legal name, address and taxpayer identification number, in a secure field. On Item E the partnership enters the SSN or ITIN for an individual and an EIN for every other partner. Collect the Form W-9 as a file, not as a number in an email.
When a W-9 is missing, the request reads "Please upload your Form W-9 through our secure portal so we can prepare your 2026 Schedule K-1," with the portal link in the same message.
Tax classification in writing. For a disregarded entity, the partnership checks the DE box in Item H2 and enters the name and TIN of the DE. Get that classification before Item E is keyed.
Profit, loss and capital percentages for Item J, based on the partnership agreement. A partner who joined, left or sold during the year also needs the closing date.
Capital account at the beginning and end of the year for Item L, and the partner's share of liabilities for Item K1, which shows nonrecourse and other recourse liabilities. List contributions, distributions, loans and guaranteed payments with dates and amounts.
The partner files a separate Form 7217 for each property distribution received, starting with tax year 2024, so get each distribution's date and property from the partnership. A partner who sells in a section 751(a) exchange must notify the partnership in writing within 30 days, or by January 15 if earlier. See Form 8308 for the exchange report.
What to collect from the partnership
The partnership agreement with all amendments, since its allocation provisions decide each partner's Item J percentages. Also get last year's Form 1065 and K-1s, since closing capital accounts become opening balances.
The year-end trial balance and financial statements, with the closing date. The trial balance should tie to the return before any K-1 is drafted.
A capital account rollforward for each partner: opening balance, contributions, distributions, allocated income and loss, and closing balance. The closing balance should equal Item L. If it does not tie to the trial balance, send the difference back before the return is prepared.
Failure modes and fixes
A partner who sold in July gets full-year percentages. Fix: split Item J at the closing date from the sale documents.
A negative capital account keyed as a negative number on the Item J capital line. Fix: enter zero on that line, because the partner instructions say the partnership enters zero when the capital account is negative or zero. Keep the real negative balance in the rollforward.
An LLC partner entered as an individual or corporation without a written classification. Fix: get the classification in writing, then use the DE box in Item H2 or an EIN in Item E.
A K-1 issued from a draft return. Fix: hold the K-1s until the trial balance ties and the return is reviewed. A corrected K-1 is a second statement the partner has to reconcile to the first.
Penalties for returns and statements due in 2026 and 2027
Late Form 1065. Under 26 U.S.C. 6698(a), the penalty runs for each partner for each month or part of a month the return is late, up to 12 months. For a return required to be filed in 2027, which is tax year 2026, the amount is $260 per partner per month under Rev. Proc. 2025-32 section 4.55. The amount for returns required to be filed in 2026, which is tax year 2025, is not restated here.
Worked example: tax year 2026, filed three months late in 2027, five partners. Five partners times 3 months is 15 partner-months, and 15 times $260 is $3,900. The 12-month limit is $3,120 per partner, so the maximum for five partners is $15,600.
Late K-1 statements. Under Rev. Proc. 2025-32 section 4.58, for statements furnished in 2027 the penalty is $60 per statement if corrected within 30 days, $130 if corrected after day 30 through August 1, and $340 if corrected after August 1 or not furnished.
For statements due in 2026, which is tax year 2025, the IRS penalties page lists the same three tiers, with $680 rather than $690 for intentional disregard.
Intentional disregard for 2027 statements is the greater of $690 or 10% of the aggregate amount of items required to be reported correctly, with no limit.
Why late K-1s drive individual extensions
A partner cannot finish a Form 1040 that depends on a pending K-1 without an estimate. Form 4868 filed by April 15, 2027 moves the filing deadline to October 15, 2027.
The extension covers filing only. The IRS says an automatic 6-month extension does not extend the time to pay, so tax owed is due by the April filing date.
When the K-1 is not final by early April, ask the partnership in writing for a marked estimate of the partner's income, deductions, credits and capital, and for its expected issue date.
The message to the partner reads "Your 2026 K-1 from [partnership] depends on the partnership return, which may not be final before April 15, 2027. Please file Form 4868 by April 15, 2027 and send us an estimated payment by the same date," so the partner's own deadline drives the decision.