Do I still need a tax ID number if I am based outside of the U.S.?
I run an online store based in India. I intend to sell physical products in USA through drop shipping model, where my vendors are based in several states of USA.
I am aware that i need to get a EIN(i have a SSN, since i lived in US earlier).
Do i need to get a Sales Tax ID, even though i am not registered in USA?
If Yes, which states should i file it from? Lets say my drop shipping vendors are based in Califaornia, Texas and my customers all over USA.
The requirement of a state sales/use permit varies depending which state your company is registered in, the states where your drop-shippers are located, and which states your customers live in.
For example, if your drop-shippers are in Texas or California, you would need to obtain sales permits for each of those states, in addition to the state your business is registered in, when applicable. (Delaware state, for example, does not charge a state sales tax).
Without understanding the full scope of your business, it's difficult to give you one direct answer. Sales tax and nexus can be tricky and depend on individual situations. I would like to point you to a question answered by Robert which explains the definitions of economic sales-tax related nexus which I believe you will find helpful.