I'm a foreigner but have been running a US single member LLC which is a disregarded entity. I need to get a US Tax Residency Certificate for this LLC. How do I get it? I know that the LLC itself, by default, is not a US tax payer. Do I have to elect my LLC to be taxed as a corporation first?
If the LLC continues to be a disregarded entity, and you as the sole owner continue to be a nonresident alien for U.S. tax purposes, then you won't be able to get a U.S. tax residency certificate.
If you file an election for the LLC to be taxed as a C corporation, then the LLC will be a regarded entity for U.S. tax purposes, and will qualify as a U.S. tax resident. Once you file the election you can go ahead and complete Form 8802 to obtain the residency certificate, if needed.