How to File a Partnership Tax Return (Form 1065)

To file a partnership tax return, you prepare Form 1065 with the partnership’s income and deductions for the year, issue a Schedule K-1 to each partner showing their share, and submit the return to the IRS by March 15 for calendar-year partnerships. The partnership itself pays no federal income tax. Everything passes through to the partners, who report their share on their individual returns and pay tax at their own rates.¹ Miss the deadline and the penalty runs $255 per partner for each month the return is late.²

Who Has to File Form 1065

Every domestic partnership must file Form 1065 for each tax year, reporting gross income, allowable deductions, and each partner’s distributive share.³ Foreign partnerships file too if they earn U.S.-source income or income connected to a U.S. trade or business. The requirement applies regardless of what tax years the individual partners use.⁴

Two narrow exceptions matter for most small businesses. A partnership with no income and no deductible or creditable expenses during the year does not have to file. And a married couple who jointly own and operate a business, both materially participate, and file a joint return can elect qualified joint venture treatment instead — reporting the income directly on their joint return and skipping Form 1065 entirely.⁵

What to Gather Before You Start

Pull the partnership’s identifying details first. You need the nine-digit Employer Identification Number; if the partnership does not have one, apply on Form SS-4 online, by fax, or by mail.⁶ You also need the North American Industry Classification System (NAICS) code that matches the business activity and the date the partnership was formed.

Then the financials. A complete profit and loss statement for the tax year covers gross receipts or sales, cost of goods sold, and itemized operating expenses like salaries, rent, repairs, and interest on business debt. A balance sheet showing total assets, liabilities, and capital accounts at the beginning and end of the year is also required. Every figure on Form 1065 ties back to these records.

Keep the partnership agreement within reach. It sets each partner’s share of profits, losses, and capital, and those allocations feed both the main form and each partner’s Schedule K-1. Organized ledgers, receipts, and bank statements let you verify the numbers and reduce the chance of follow-up from the IRS.

Filling Out Page 1 of Form 1065

Page one captures the partnership’s overall financial picture. Enter gross receipts or sales on the income lines, subtract cost of goods sold to get gross profit, then list deductible expenses: salaries and wages paid to employees, guaranteed payments to partners, rent, taxes, interest, depreciation, and other ordinary business costs.

Line 22 totals allowable deductions. Line 23 subtracts that total from gross profit to produce the partnership’s ordinary business income or loss for the year.⁷ That figure flows to Schedule K and is ultimately divided among the partners. Some income categories stay off page one: rental income, portfolio income like interest and dividends, and capital gains are reported separately on Schedule K so partners can apply the correct tax treatment on their own returns.⁸

Enter total assets on page one if they are $250,000 or more. The form is available on the IRS website and through tax preparation software.¹

Schedule K and the K-1 for Each Partner

Schedule K summarizes every partner’s combined share of partnership income, deductions, and credits. It has separate lines for ordinary business income, net rental real estate income, guaranteed payments, interest, dividends, royalties, capital gains and losses, and various credits.⁸ The Schedule K totals must match the amounts on page one and the other supporting schedules.

Each partner then receives a Schedule K-1 breaking out their individual share of every item on Schedule K. The K-1 shows the partner’s identifying number (Social Security Number for individuals, EIN for entities) and their percentage of profit, loss, and capital at the beginning and end of the year.⁹ Those percentages come from the partnership agreement and drive the exact dollar amounts allocated.

The K-1 also reports each partner’s share of credits, charitable contributions, and liabilities. Liabilities are split between recourse (a partner is personally on the hook) and nonrecourse (no partner bears the economic risk of loss). That split affects the partner’s tax basis, which limits how much of any loss they can deduct on their personal return.⁹ The partnership must give each partner their K-1 by the same date Form 1065 is due.⁵ The K-1 also reports what each partner needs to calculate the Section 199A qualified business income deduction on their individual return.

Deadlines and Extensions

Form 1065 is due by the 15th day of the third month after the partnership’s tax year ends. For calendar-year partnerships, that means March 15.⁵ When the 15th falls on a weekend or federal holiday, the deadline moves to the next business day. For the 2025 tax year (filed in 2026), the due date is March 16, 2026, because March 15 is a Sunday.

Need more time? File Form 7004 on or before the original due date to get an automatic six-month extension.¹⁰ For a calendar-year partnership, that pushes the deadline to September 15. Form 7004 extends time to file, not time for any partner to pay individual income tax on partnership income. Partners who expect to owe should still make estimated payments on the regular schedule to avoid personal underpayment penalties.

How to Submit the Return

Partnerships can e-file Form 1065 through the IRS Modernized e-File (MeF) system, which returns an electronic acknowledgment confirming receipt.¹¹ For many partnerships, e-filing is required rather than optional. Partnerships with more than 100 partners must e-file. Smaller partnerships must also e-file if they file 10 or more returns of any type during the year, counting income tax, employment tax, excise tax, and information returns together.⁵

Partnerships not required to e-file can mail paper returns to the IRS service center for their region. Using a designated private delivery service gives you a documented mailing date, which counts as the filing date for penalty purposes. The IRS publishes the approved delivery services on its website.

What Partners Owe on Their Own Returns

The partnership does not withhold income tax or employment tax from partner distributions. Each partner handles their own self-employment tax on their share of business earnings. For general partners, the entire distributive share of ordinary business income is subject to self-employment tax, whether or not the cash was actually distributed.¹² Limited partners pay self-employment tax only on guaranteed payments received for services, not on their distributive share.

Partners also owe quarterly estimated tax payments if they expect to owe $1,000 or more when they file. The four due dates for individuals are April 15, June 15, September 15, and January 15 of the following year. To avoid an underpayment penalty, pay at least the smaller of 90% of your current-year tax or 100% of last year’s tax. If your prior-year adjusted gross income exceeded $150,000 ($75,000 if married filing separately), the prior-year safe harbor rises to 110%.¹³ New partners receiving a first K-1 midyear should adjust remaining estimates to reflect the added income.

Penalty for Filing Late

A partnership that files Form 1065 late, or files an incomplete return, faces a penalty for each month the failure continues, up to 12 months.¹⁴ For returns due after December 31, 2025, the penalty is $255 per partner per month.² Multiply $255 by the number of people who were partners at any time during the year, then by the number of months (or partial months) the return is overdue.

A four-partner partnership filing three months late owes $255 × 4 × 3 = $3,060. The 12-month cap for that partnership is $255 × 4 × 12 = $12,240. The IRS can waive the penalty for reasonable cause, but applies that exception narrowly.²

Fixing an Error After Filing

How you correct a filed return depends on whether the partnership is under the centralized audit rules from the Bipartisan Budget Act (BBA). Most partnerships with tax years beginning after 2017 are. BBA partnerships correct errors by filing an administrative adjustment request (AAR) on Form 8082, or Form 1065-X for paper-filed returns.¹⁵

On the partner side, a K-1 you believe is wrong still has to be reported consistently with how the partnership reported it, unless you file Form 8082 with your individual return to flag the inconsistency.¹⁶ That applies whether you disagree with the dollar amount or the tax treatment (say, income labeled as capital gain that you believe is ordinary). If the partnership has not given you a K-1 by your own filing deadline, file using your best estimate of the partnership items and attach Form 8082 explaining the situation.

If the Partnership Has Foreign Partners

A partnership allocating income effectively connected with a U.S. trade or business to foreign partners has extra obligations under Section 1446. The partnership must withhold at the highest individual rate for foreign partners who are individuals, or at the highest corporate rate for foreign partners that are corporations.¹⁷ Report the withheld amounts on Form 8804, with a Form 8805 for each foreign partner showing their share.¹⁸ When a foreign partner sells or transfers a partnership interest and the gain would be effectively connected income, the buyer generally must withhold 10% of the total amount paid. Partnerships with any foreign partners should work with a tax professional to be sure these forms are filed alongside Form 1065.

1
Internal Revenue Service. About Form 1065, U.S. Return of Partnership Income
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Internal Revenue Service. Failure to File Penalty
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Office of the Law Revision Counsel. 26 USC 6031 – Return of Partnership Income
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eCFR. 26 CFR 1.6031(a)-1 – Return of Partnership Income
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Internal Revenue Service. 2025 Instructions for Form 1065
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Internal Revenue Service. About Form SS-4, Application for Employer Identification Number
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Internal Revenue Service. Form 1065 (2025)
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Internal Revenue Service. Instructions for Form 1065 (2025)
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Internal Revenue Service. 2025 Partners Instructions for Schedule K-1 (Form 1065)
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Internal Revenue Service. Instructions for Form 7004
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Internal Revenue Service. Modernized e-File (MeF) for Partnerships
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Internal Revenue Service. Self-Employment Tax and Partners
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Internal Revenue Service. Estimated Taxes
14
Office of the Law Revision Counsel. 26 USC 6698 – Failure to File Partnership Return
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Internal Revenue Service. File an Administrative Adjustment Request for a BBA Partnership
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Internal Revenue Service. Instructions for Form 8082
17
Office of the Law Revision Counsel. 26 USC 1446 – Withholding of Tax on Foreign Partners Share of Effectively Connected Income
18
Internal Revenue Service. About Form 8804, Annual Return for Partnership Withholding Tax (Section 1446)