Since I created my LLC May 10, 2023. I must file Form 2553 now before year ends in 2023?
the LLC tax year began 5/10/23 so 2 months 15 days would be on or brfore 7/25/2023. However, to be honest, the IRS is generous in allowing late elections.
When I file my LLC as S Corp, do I file 1120S?
for the years the S-Corp election is in effect you file 1120S. That requires Turbotax Business (full Windows PC. - not available for MAC or online) the S-Corp issues a K-1 which then gets reported on your 1040. Are you familiar with the need to take a salary? if not you should discuss the operations of the S-Corp with a tax pro.
