Preparation and electronic filing of U.S. tax returns typically requires a preparer tax identification number (PTIN) and an electronic filing identification number (EFIN). A PTIN is a unique identifier assigned by the Internal Revenue Service (IRS) to tax professionals who prepare federal tax returns for compensation. An EFIN is an identification number assigned by the IRS to tax professionals and companies who are authorized to electronically file federal tax returns. To obtain a PTIN, tax professionals must complete a brief application process through the IRS website and provide basic personal and professional information. To obtain an EFIN, tax professionals must complete a longer application process that includes an IRS review of the preparer's tax compliance history and background check. Once a PTIN and EFIN have been obtained, tax professionals can use them to electronically file federal tax returns for their clients through the IRS e-file program. This process is typically faster and more convenient than paper filing and can provide a confirmation of receipt from the IRS in a matter of minutes. It's important to note that tax professionals are held to certain standards and requirements for preparing and electronically filing tax returns, including obtaining continuing education, following ethical standards, and complying with federal and state tax laws. Violation of these standards can result in penalties and the loss of the PTIN and EFIN.