Pass-through reporting
A partnership is not a taxable entity for federal income tax purposes. Form 1065 reports the partnership's ordinary business income or loss, separately stated items, and balance sheet, then issues each partner a Schedule K-1 showing their distributive share. Partners report the K-1 amounts on their own Form 1040 (or 1120, 1041, etc.).
Due date
Form 1065 is due the 15th day of the third month after year-end — March 15 for calendar-year partnerships. A six-month extension to September 15 is available with Form 7004. The earlier due date (compared with individual returns) gives partners time to receive K-1s before their own April 15 deadline.
Schedule K and K-1
Schedule K reports the partnership's totals for ordinary income, rental income, interest, dividends, capital gains, Section 179 expense, charitable contributions, and many other line items. Schedule K-1 allocates each item to each partner according to the partnership agreement. Partners must report their K-1 items even if no cash was distributed.
Self-employment income for partners
A general partner's distributive share of ordinary partnership income is generally subject to self-employment tax. Limited partners are subject to SE tax only on guaranteed payments. The treatment of LLC members is more nuanced — recent IRS guidance and tax court cases have narrowed the "limited partner" exception when members actively manage the LLC.
Centralized partnership audit regime
Under the BBA centralized partnership audit regime, audit adjustments are generally assessed at the partnership level unless the partnership elects out (only available for small partnerships of 100 or fewer eligible partners). Partnerships should designate a "partnership representative" with binding authority on Form 1065.
Software vs. paper filing
Most filers use commercial tax software or a tax preparer to handle Form 1065, U.S. Return of Partnership Income — and that is the right call for nearly all small-business returns. The IRS Free File program is open to taxpayers below an annually adjusted income limit and supports most small-business forms. Direct paper filing is technically still an option but is slower, more error-prone, and increasingly relegated to corner-case situations. Whichever path you choose, retain a digital PDF of the as-filed return for at least three years (six if you under-reported income by more than 25%).