Historically, the IRS has said that a disregarded entity could (and maybe should) use the owner’s taxpayer identification number for income and other tax purposes. For employment tax reporting, the IRS issued Notice 99-6, 1999-1 CB 321 , which said that employment taxes for employees of a disregarded entity could be reported by a disregarded entity in one of two ways:
(1) Calculation, reporting, and payment of all employment tax obligations with respect to employees of a disregarded entity by its owner (as though the employees of the disregarded entity are employed directly by the owner) and under the owner’s name and taxpayer identification number; or
(2) Separate calculation, reporting, and payment of all employment tax obligations by each state law entity with respect to its employees under its own name and taxpayer identification number.