Filling out a W9 as a Single Member LLC

I previously operated my consulting business as a sole proprietor operating under my own name, using my SSN on W9 forms, etc. I have since registered an LLC and am starting to bring in clients. I have not elected this LLC to corporate status.

In 2011, the W-9 form changed its format and the "Limited Liability Company" tax classification no longer allows for the option "D" for disregarded entities. According to this website, I am to fill out the W-9 using my own information and SSN as a sole proprietor.

There is also the option to provide an EIN instead of a SSN, which I'd rather do simply to ensure the safety of my SSN. However, this EIN has to be associated with the entity on the "Name" line, not the "Business Name," so I can't use the EIN of my LLC here.

My next step was to apply for a sole proprietor's EIN at the IRS website, and here's where the trouble started. According to the IRS EIN application page:

A sole proprietor is one individual who owns a company that is not incorporated or registered with the state as a limited liability company (LLC). Sole proprietors may or may not have employees.

Maybe I'm mixing up my entities here, but I'd really like a bit of clarification.

I ended up calling the IRS, who's friendly representative admitted that the new W-9 is a bit confusing for SMLLCs. They instructed me to simply fill out my own name on in the name box, the LLC's name in the business name box, and the EIN of the LLC in the EIN box.

I called them as well, but I was told to write "Single Member LLC" in "Other" field and use my LLC's EIN.

As of January 8, 2015, the W-9 form is very specific -- and probably more up-to-date than older answers by James and Eddy. See page 3, Part I.

Part I. Taxpayer Identification Number (TIN)

Enter your TIN in the appropriate box. If you are a resident alien and you do not have and are not eligible to get an SSN, your TIN is your IRS individual taxpayer identification number (ITIN). Enter it in the social security number box. If you do not have an ITIN, see How to get a TIN below.

If you are a sole proprietor and you have an EIN, you may enter either your SSN or EIN. However, the IRS prefers that you use your SSN.

If you are a single-member LLC that is disregarded as an entity separate from its owner (see Limited Liability Company (LLC) on this page), enter the owner’s SSN (or EIN, if the owner has one). Do not enter the disregarded entity’s EIN. If the LLC is classified as a corporation or partnership, enter the entity’s EIN.

Note. See the chart on page 4 for further clarification of name and TIN combinations.

I'm not an accountant or a lawyer, but I think if you read it carefully it is clear.

Other answers have mentioned inconsistencies. It may be that the rules have changed over time (I've seen an article suggesting that there was a change in December 2011).

I know this is a bit old but I wanted to reiterate that the EIN you enter on your W9 cannot be your LLC's EIN. It has to be your own EIN as sole proprietor. That can be confusing.