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Received a CP2100 or CP2100A?

Did you know that a mismatched TIN and name combination is something you can be fined for?
If you submit a mismatched name/TIN combination on your W-2 or 1099 filings, the IRS will issue a CP2100 or CP2100A Notice to you if the payee's name and Taxpayer Identification Number (TIN) on your filed information return do not match with IRS records. You will then have to obtain the correct information and be able to prove that you tried to and if unsuccessful, start withholding funds on all future payments.
The IRS recommends that you annually collect W-9s for all your independent contractors. To help with that process, we now offer a service where we will email your contractors, they complete the W-9 form electronically, and their information is saved in your account as a recipient.
So why wait? Use our TIN Matching and/or W-9 services today and save yourself the trouble and costly headaches of mismatches regardless if you use our e-filing services or not! Simply import your payer and recipient information and get started today.

For many businesses, March 16, 2026 (since March 15 falls on a Sunday) is an important federal tax deadline. The main reason is that calendar-year pass-through entities must file earlier than individuals and C corporations so owners can receive their tax information in time to file their personal returns.

Key Business Tax Deadlines – March 16, 2026

1. Partnerships
• Form 1065 – U.S. Return of Partnership Income
• Applies to partnerships and most multi-member LLCs taxed as partnerships
• Schedule K-1s must be provided to partners by this date

2. S Corporations
• Form 1120-S – U.S. Income Tax Return for an S Corporation
• Schedule K-1s issued to shareholders

These returns are due the 15th day of the 3rd month after the end of the tax year (for calendar-year entities, that’s March 15; when it falls on a weekend, it moves to the next business day).

If the Return Isn’t Ready

Entities can file Form 7004 to request an extension:
• Partnerships & S Corps → automatic 6-month extension to September 15, 2026

Important note:
• The extension is for filing, not for paying any tax that may be due.

Why the Earlier Deadline Exists

Congress moved partnership and S-corp deadlines earlier in 2015 (PATH Act) so that:
• Owners receive K-1s earlier, and
• Individuals can complete their Form 1040 filings by April without waiting on pass-through information.

✅ In short: March 15 (or the next business day) is primarily about 1065 and 1120-S filings and issuing K-1s.