Resources
Helpdesks, customer service lines, helpful federal and state website links, and links to important forms, reports, and documentation.
Customer Service Numbers
IRS Enterprise Computing Center at Martinsburg, WV
Customer Service Number: (866) 455-7438, M-F 8:30 am - 4:30 pm EST
Customer Service Email: mccirp@irs.govIRS efile Services Help Desk: (866) 455-7438
EFTPS Customer Service for federal tax deposits: (800) 945-8000
Website Links
IRS Forms and Publications page for looking up forms and publications.
IRS FIRE System login page for online filing, and filing extensions, for Forms 1099, 1098, 5498, W-2G, 1042-S. To learn more, visit the IRS Filing Information Returns Electronically (FIRE) page.
IRS AIR System page for online filing of Forms 1095-B, 1094-B, 1095-C, 1094-C information returns required under the Affordable Care Act.
IRS TIN Matching information and application page to learn about and apply for the IRS’ free validation service for Name-TIN furnished by a customer, vendor or other payee, available to those who file Forms 1099-B, 1099-DIV, 1099-INT, 1099-K, 1099-MISC, 1099-OID or 1099-PATR.
IRS Tax Treaties page to find PDF copies of income tax treaties between the U.S. and foreign tax jurisdictions, plus Technical Explanation papers that clarify provisions of treaties.
IRS Tax Treaty Tables page to look up tables that were in IRS Publication 515 in past years are now available only on the IRS website. The IRS now displays an LOB Table covering Limitation on Benefits provisions found in tax treaties.
Links to PDF Documents
IRS Publication 1281 guide to backup withholding of federal income tax and the IRS "B Notice" requirements (current version of Publication 1281 is the one dated 3-2020).
NOTE that Pub. 1281 doesn't show the current Form W-9! Obtain the current Form W-9 (revised October 2018) from the IRS website.
IRS Publication 1586 guide to the "reasonabe cause" regulations and IRS Notice 972CG for proposed penalties that include filing forms with incorrect or missing Taxpayer Identification Numbers (current version of Publication 1586 is the one dated 08-2018).
IRS Publication 1220 provides instructions and specifications for electronic filing of Forms 1099, 1098, 5498, W-G, 1097-BTC, 3921, 3922.
IRS Publication 1187 provides instructions and specifications for electronic filing of Form 1042-S.
Revenue Procedure 99-50 Combined information reporting after merger or acquisition
Revenue Procedure 97-22 Electronic storage of books and records
Revenue Procedure 97-33 EFTPS procedures (Electronic Federal Tax Payment System)