Some states may have used similar numbering for their own forms (e.g., Illinois previously used Form IL-8633-B, which has also been discontinued in favor of an online portal). Where to Find the PDF for Reference

Generally considered outdated or discontinued for federal purposes; the last official paper revision was in July 2003.

While the form is no longer accepted for new applications, you can still download archived versions for informational purposes or record-keeping: Download Form 8633 (Archive) from IRS.gov. Accessible Form 8633 version from IRS.gov.

Generic fillable templates are also hosted on third-party sites like pdfFiller and DocHub , though these should not be used for actual IRS submissions. Form 8633 - IRS

Tax professionals must register for e-services on the official IRS website to submit their application electronically.

Historically used to obtain an Electronic Filing Identification Number (EFIN) and ETIN.