Find IRS forms, instructions, publications, and notices for prior years back to 1864. If a PDF file won't open, try downloading the file to your device and opening it using Adobe Acrobat. View more information about Using IRS Forms, Instructions, Publications and Other Item Files. Click on a column heading to sort the list by the contents of that column. Enter a term in the Find box Click the Search button Showing 1 - 2 of 2Find Help Find Prior Year » RegExReplace » Product Number Prior Year » Revision Date Prior Year » Title Show per page 2550100200 SearchClear Product Number Title Revision Date Form 8821 (sp) Tax Information Authorization (Spanish Version) 2021 Instruction 8821 (SP) Instructions for Form 8821, Tax Information Authorization (Spanish Version) 2021