An EIN is the nine-digit Employer Identification Number the IRS assigns to business entities. Whether you use it instead of an SSN on a 1099 depends entirely on the payee's tax classification. The W-9 tells you which number to use. Reading it correctly prevents TIN mismatches and CP2100 notices.
An EIN is an Employer Identification Number. The IRS issues it to business entities: corporations, partnerships, multi-member LLCs, nonprofits, trusts, and estates. It identifies the entity for federal tax purposes the same way a Social Security Number identifies an individual.
EINs follow the format XX-XXXXXXX (for example, 12-3456789). You apply for one using Form SS-4. Online applications through IRS.gov issue the EIN immediately.
The term EIN and FEIN (Federal Employer Identification Number) refer to the same number. Both are correct.
Use the EIN on a 1099 when the payee is a business entity that files its own federal tax return: a corporation, a partnership, or a multi-member LLC taxed as a partnership.
Use the SSN when the payee is an individual filing on their personal return. For a sole proprietor, that is always the owner's SSN. For a single-member LLC, the default is the owner's SSN: but there is an exception.
| Payee type | TIN to use on 1099 | What to enter on Line 1 and TIN field of W-9 |
|---|---|---|
| Individual / sole proprietor | SSN | Owner's legal name; their SSN |
| Single-member LLC (disregarded entity, no corporate election) | Owner's SSN or the LLC's own EIN | Owner's name on Line 1; LLC name on Line 2; owner's SSN or the LLC's own EIN in Part I. IRS prefers the SSN. |
| Single-member LLC taxed as C corp or S corp | LLC's EIN | LLC name on Line 1; check LLC box with C or S code; LLC's EIN in Part I |
| Multi-member LLC taxed as partnership | LLC's EIN | LLC name on Line 1; check LLC box with P code; LLC's EIN in Part I |
| C corporation or S corporation | Corporation's EIN | Corporation's legal name on Line 1; check C Corp or S Corp box; EIN in Part I |
| Partnership | Partnership's EIN | Partnership's name on Line 1; check Partnership box; EIN in Part I |
The W-9 controls what you report. Whatever name and taxpayer identification number (TIN) the payee certifies on their W-9 is exactly what you put on the 1099: nothing more, nothing less. Your job is to copy that information accurately, not to second-guess it or fill in what you think is correct. If something on the W-9 looks wrong or incomplete, don't fix it yourself. Send it back to the payee and ask them to submit a corrected W-9 before you file.
Single-member LLCs cause more TIN confusion than any other payee type. Here is why.
By default, a single-member LLC is a disregarded entity for federal income tax purposes. The IRS treats the LLC as the same tax person as its individual owner. Income and expenses flow directly to the owner's Form 1040, Schedule C.
Because the IRS treats a disregarded entity as its owner, the W-9 instructions say the owner's name goes on Line 1, the LLC name goes on Line 2, and the TIN in Part I should be the owner's SSN. The IRS prefers the SSN for disregarded entities.
The June 2026 revision of Form W-9 states: 'Do not enter the employer identification number (EIN) of a disregarded entity.' The LLC's own EIN is not the correct TIN for a disregarded single-member LLC when the owner is an individual. The owner's SSN is.
The exception: if the single-member LLC has obtained its own EIN (which many do, for payroll purposes or to protect the owner's SSN from exposure), that EIN may be used instead. IRS Publication 3402 confirms that a disregarded entity LLC owned by an individual may provide the owner's SSN or EIN, not the LLC's EIN unless that EIN was obtained for the LLC's own activities.
In practice: use whatever the contractor certified on their W-9. If they checked Individual/sole proprietor and gave their SSN, use the SSN. If they checked Individual/sole proprietor and gave an EIN for the LLC, use that EIN. Do not ask them to change a validly completed W-9.
A sole proprietor can have their own EIN separate from any LLC. They may have obtained it to open a business bank account, hire employees, or for other administrative reasons. This EIN belongs to them as an individual operating as a sole proprietor.
A single-member LLC can also have its own EIN, obtained specifically for the LLC entity.
These two EINs are different numbers. The IRS links both back to the owner's SSN, but they are separate identifiers. On a W-9 for a disregarded single-member LLC, the correct TIN is the owner's SSN or the owner's individual EIN, not the LLC's separate entity EIN.
If you receive a W-9 with an EIN and you are not sure which type of EIN it is, ask the contractor to clarify. The safest approach is to request the W-9 be completed with the owner's SSN for a disregarded entity.
Yes. The IRS matches the name and TIN combination on your 1099 against its records. If the name on the 1099 does not match what the IRS has registered to that TIN, it triggers a mismatch.
A mismatch results in a CP2100 or CP2100A notice. You then have to work through the B-Notice process, send the contractor a solicitation for a corrected W-9, and potentially begin backup withholding at 24 percent.
The most common single-member LLC mismatch: the owner certified their LLC's entity EIN on the W-9, you filed the 1099 with the owner's name and that EIN, and the IRS records show that EIN registered to the LLC name, not the individual owner's name. The name and TIN do not match.
Look at two things: Line 3 (federal tax classification) and Part I (the TIN field).
Whatever the W-9 says, enter that name and TIN combination into Tax Forms Helper exactly as given. The IRS matches on the combination, not on the TIN alone.
If you receive a W-9 that appears to have the wrong TIN for the entity type (for example, a sole proprietor who gave an EIN when their name is in Line 1), you can ask for clarification. You cannot require the payee to change a W-9 that is technically valid.
If the payee confirms the information is correct, file the 1099 with the name and TIN as given. If the combination later generates a CP2100 notice, you have documentation that you followed the W-9 as provided.
Use TIN Check Service in Tax Forms Helper to verify any name and TIN combination against IRS records before you file. See TIN Check Service for how to add it to your eFile order.
Your payee records have the right TIN for each entity type. Your 1099 filings go through without mismatches.
Use the EIN when the payee is a business entity that files its own federal tax return: a corporation, a partnership, or a multi-member LLC taxed as a partnership. Use the SSN when the payee is an individual filing on their personal return, which for a sole proprietor is always the owner's SSN. The W-9 controls which number you report.
Yes. EIN stands for Employer Identification Number and FEIN for Federal Employer Identification Number, and both refer to the same number the IRS issues to business entities. Both terms are correct. EINs follow the format XX-XXXXXXX and are requested using Form SS-4, with online applications through IRS.gov issuing the number immediately.
The owner's SSN by default. A single-member LLC is a disregarded entity, so the W-9 instructions put the owner's name on Line 1, the LLC name on Line 2, and the owner's SSN in Part I. The June 2026 revision of Form W-9 states that you should not enter the EIN of a disregarded entity. If the LLC obtained its own EIN, that EIN may be used instead, and in practice you report whatever the contractor validly certified.
The IRS matches the name and TIN combination against its records, and a mismatch produces a CP2100 or CP2100A notice. You then work through the B-Notice process, send the contractor a solicitation for a corrected W-9, and potentially begin backup withholding at 24 percent. Running TIN Check Service before you file verifies the combination while a fix is still simple.
Subject to change. Verify at IRS.gov or the relevant government site.
Use the EIN when the payee is a business entity that files its own federal tax return: a corporation, a partnership, or a multi-member LLC taxed as a partnership. Use the SSN when the payee is an individual filing on their personal return, which for a sole proprietor is always the owner's SSN. The W-9 controls which number you report.
Yes. EIN stands for Employer Identification Number and FEIN for Federal Employer Identification Number, and both refer to the same number the IRS issues to business entities. Both terms are correct. EINs follow the format XX-XXXXXXX and are requested using Form SS-4, with online applications through IRS.gov issuing the number immediately.
The owner's SSN by default. A single-member LLC is a disregarded entity, so the W-9 instructions put the owner's name on Line 1, the LLC name on Line 2, and the owner's SSN in Part I. The June 2026 revision of Form W-9 states that you should not enter the EIN of a disregarded entity. If the LLC obtained its own EIN, that EIN may be used instead, and in practice you report whatever the contractor validly certified.
The IRS matches the name and TIN combination against its records, and a mismatch produces a CP2100 or CP2100A notice. You then work through the B-Notice process, send the contractor a solicitation for a corrected W-9, and potentially begin backup withholding at 24 percent. Running TIN Check Service before you file verifies the combination while a fix is still simple.
Save up to 45 days by skipping the wait for IRS processing.
Save up to 45 days by skipping the wait for IRS processing.
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Social Security Administration Direct Operations CenterWilkes-Barre, PA 18769-0001 (for Certified Mail Use ZIP code 18769-0002)
Social Security Administration Direct Operations CenterP.O. Box 3333 Wilkes-Barre, PA 18767-3333.
Reduce the 250-return threshold enacted in prior regulations to generally require electronic filing by filers of 10 or more returns in a calendar year. The final regulations also create several new regulations to require e-filing of certain returns and other documents not previously required to be e-filed.
Require filers to aggregate almost all information return types covered by the regulation to determine whether a filer meets the 10-return threshold and is required to e-file their information returns. Earlier regulations applied the 250-return threshold separately to each type of information return covered by the regulations.
Eliminate the e-filing exception for income tax returns of corporations that report total assets under $10 million at the end of their taxable year, and require partnerships with more than 100 partners to e-file information returns, and they require partnerships required to file at least 10 returns of any type during the calendar year to e-file their partnership return.
Corrections must be filed the same way the original was submitted. If you eFile the original then you must eFile the correction. If you mailed in the original then you must mail in the correction.
Do not cut or separate Copies A of the forms that are printed two or three to a sheet, except for Form W-2G. Generally, Forms 1097, 1098, 1099, 3921, 3922, and 5498 are printed two or three to an 8" x 11"sheet. Form 1096 is printed one to an 8" x 11" sheet.
These forms must be submitted to the IRS on the 8" x 11" sheet. If at least one form on the page is completed, you must submit the entire page. Forms W-2G are an exception and may be separated and submitted as single forms. Send your forms to the IRS in a flat mailing (not folded).
Do not staple, tear, or tape any of these forms. It will interfere with the IRS’s ability to scan the documents.
Pinfeed holes on the form are not acceptable. Pinfeed strips outside the 8" x 11" area must be removed before submission without tearing or ripping the form. Substitute forms prepared on continuous feed or strip form paper must be burst and stripped to conform to the size specified for a single sheet (8" x 11") before they are filed with the IRS.
Do not use a form to report information that is not properly reportable on that form. If you are unsure of where to report the data, call the information reporting customer service site at 1-866-455-7438 (toll free).
Do not submit anything other than red ink copies to the IRS.
Use the official forms or substitute forms that meet the specifications in Pub. 1179. If you submit substitute forms that do not meet the current specifications and that are not scannable, you may be subject to a penalty for each return for improper format. All of Adam’s tax forms meet the proper requirements, so use us as a resource.
Do not use dollar signs ($) (they are pre-printed on the forms), ampersands (&), asterisks (*), commas (,), or other special characters in money amount boxes.
Do not use apostrophes (’), asterisks (*), or other special characters on the payee name line.
No photocopies of any form are acceptable.
Do not print plain ink copies of your W-2 copy A or W-3 form. If a box doesn't apply to you, leave it empty.
Do not add "0".
Do not omit the decimal point and cents from entries.
Do not mistakenly check the “Retirement plan” checkbox in box 13. See page 22 of this IRS PDF for Retirement plan details.
Do not misformat the employee’s name in box e. Enter the employee’s first name and middle initial in the first box; his or her surname in the second box; and his or her suffix (such as “Jr.”) in the third box (optional).
Do not enter the incorrect employer identification number (EIN) or the employee’s SSN for the EIN.
Do not cut, fold or staple Copy A paper forms mailed to SSA.
Do not mail any copy other than Copy A of Form W2 to the SSA.
File the correct form with the correct amount, code, checkbox, name or address, and check the “CORRECTED” box. This overwrites what you originally filed with the IRS under that person or company’s name and TIN. Send the corrected form to the recipient and prepare the red Copy A to send to the IRS with the Form 1096 transmittal if you’re paper filing. If you also had the wrong recipient/payee name or TIN do a Type 2 correction instead.
For Type 2 errors, either the recipient/payee name and/or the TIN are wrong or you used the wrong form (like a 1099-MISC instead of a 1099-NEC). Action: This is a two-step process. First, you must zero out what you filed with the IRS under the wrong name/TIN and then file the new form.
Step 1
File a form with the CORRECTED box checked and the exact same payer and recipient information as on the incorrect form, but with all the amounts as zeros. This will remove the originally filed form from the IRS records.
Step 2
File a new Form 1099 with the right information as an originally filed form (not a corrected form).
Incorrect Payer Name, Payer TIN, or both Action: Write a letter to the IRS.
If you filed with the wrong payer name (yours or your client’s name/company name) or the wrong payer taxpayer identification number (TIN), you don’t need to send in a corrected form.
Instead, you should write a letter containing the following information:
Name and address of the payer
Type of error (including the incorrect payer name/TIN that was reported)
Tax year Payer TIN Transmitter Control Code (if you eFiled),
Type of return, Number of payees, Filing method (paper or eFiling)
You have exceeded the IRS paper filing threshold and are required to file electronically.
