I'm at the point where I need to fill out a tax interview. While filling out the forum after I clicked Registering as a "Corporation, Trust, Partnership or LLC (other than a single-member LLC)" Now, I have incorporated my corporation, and when checking all of my documents I never came across anything called a "Company registration number" specifically, and the closest thing I have found was an Entity ID/ Identification Number. So what I'm really asking is if the Company registration number and  Entity ID/ Identification Number are the same, and if not, how would  find my Company registration number so I can continue on with the interview?

Thanks in advance 

Btw I live in the U.S.