B1 -> H1B in USA... Confused?!!!

B1 -> H1B in USA... What to do next?

I came on B1 and then before it was expired I applied for H1B. Got approved just recently. I am not sure I understand how does it work... SHould I start working the next day after it was approved?
How do I get SS number or A number?
How do I pay taxes and etc..
My company doesn't really know as I am the first foreign employer they have.
Had anybody been in my situation before?
Appreciate you help!!!

B1 -> H1B in USA... What to do next?

I came on B1 and then before it was expired I applied for H1B. Got approved just recently. I am not sure I understand how does it work... SHould I start working the next day after it was approved?
How do I get SS number or A number?
How do I pay taxes and etc..
My company doesn't really know as I am the first foreign employer they have.
Had anybody been in my situation before?
Appreciate you help!!!

I am not an expert, but I think you technically need to be employed by your sponsor as soon as possible. If you don't have a SS# yet, I am not sure they can really put you on their books. Therefore, the first thing you need to do is go to the Soc Sec office with your original Notice of Approval from the INS, and also bring your passport and any other related documentation. (Maybe you'd better call first to find out exactly what you need). Once you get it you can start working. You may be able to start working without it and have them put a blank SS# until you get it in their system, and then they can just put it in after you get it, but I'm not sure they're allowed to do it. As far as taxes, just tell the payroll dept. to withhold taxes the same as any other employees. You will need to file a 1040-NR by 4/15 of each year with the IRS, just like any American employee.

I hope this helps.

Kramer

thank's a lot!