The W9 is tricky for an LLC to fill out but let's simplify some of it here.
An LLC that is it's own tax entity therefore...
Those would be a C-corporation, an S-corporation or a partnership as an example.
The IRS instructions say that you should not check the Limited Liability Company box.
You would fill in the LLC's name and it's FID number then make a check mark in the proper tax classification box. Those would be C-corporation, an S-corporation or a partnership.
You own the LLC as a member and a you are a single person.
Therefore you put in the owners social-security number rather than the LLC's FID number.
You should write in the name of the owner in the "Name" section and fill in the name of the business on the "Business" name section.
You would have to put in the tax classification of the owner if the LLC is owned by a single member.
If one LLC is owned by another LLC then put in the tax classification of the parent LLC and add a check mark to the LLC box.
A lot of folks panic when they are asked to fill out a W9 form.
My first episode with one left me with a feeling of confusion because I did not read the instructions to be sure of what I was doing.
I just had at it without reading anything and it was overwhelming - never again.
Take a little time to read the instructions and it is very simple to deal with.
Now when I fill one out I simply do it in about a minute.
It gets very simple to deal with these and if you do them often enough it is a breeze!