IRS Form 1065, also known as the "U.S. Return of Partnership Income," is a crucial tax document used by partnerships, including limited liability partnerships (LLPs) and limited liability companies (LLCs) classified as partnerships for tax purposes. It declares the profits, losses, deductions, and credits of a business partnership. Filing Form 1065 is a fundamental requirement for partnership entities to report their financial information to the Internal Revenue Service (IRS).

In addition to Form 1065, partnerships must also submit Schedule K-1, a document prepared for partners, which outlines their share of the partnership's income and losses.