The Internal Revenue Service publishes its own instructional booklet on how to complete the Form 1040 at IRS.gov. Contents include filing requirements, line-by-line walkthroughs of each component of Form 1040, and information on tax refunds and general tax issues such as interest and penalties.
The IRS also publishes "Your Federal Income Tax," a guide for individual taxpayers that includes high-level overviews and explanations of tax issues. Third-party resources include "A Step-by-Step Guide to the 1040," by the New York Times, as well as "Wiley Tax Preparer: A Guide to Form 1040" for professional tax preparers. Individuals with questions about how to complete their tax returns also have access to direct support from the IRS and its affiliates, including telephone assistance and volunteer clinics, according to the IRS website.