Should I put my EIN number or my personal social security number on a W9 form when I have a single person LLC and it does have an EIN number?

I have a LLC setup and I am the only employee. My LLC was assigned an EIN number. However, I am not an S or C corp, or a partnership. I don't know if I should put the LLC's EIN number on a W9 form if the IRS is going to file me as a sole proprietor anyhow. What should I do?