Hi

Currently I am working on H1B visa. My wife and kid are in india, and probably they may not join with me in this year. Following are my questions
1. While filing the tax returns this year, should I file as single or can I file jointly
2. If I can file jointly, what are the supporting documents required for my wife?
3. Can I claim my wife and son as dependents?

Please answer my questions

Thanks
Subramanyam Alur

If you have completed substantial presence test (that is you are resident for tax purpose), then you can only file resident return as married filing separately or married filing jointly. You can file joint return even when your spouse has never been to the U.S. Your U.S. Tax Return: The U.S. Visas (http://taxipay.blogspot.com/2008/08/us-visas.html)

You can not claim you son as dependent unless he is U.S. resident or present in the U.S. any time in 2009.

A spouse is never a dependent.

If you want to file jointly you MUST get your wife an ITIN number. You do this by filing a W-7; get a copy here:
http://www.irs.gov/pub/irs-pdf/fw7.pdf

Check box (e) and fill in your name and SS number.
Your wife will need to get a certified copy of her passport. See thread:

https://www.askmehelpdesk.com/taxes/regarding-photocopies-itin-application-403898.html

When you file taxes next year submit the W-7 and all required documents as well as your return to:
Internal Revenue Service
ITIN Operation
P.O. Box 149342
Austin, TX 78714-9342

You both will claim the 6013(g) election and the worldwide income of you both will exposed to US taxation. See Publication 519, page 10:
http://www.irs.gov/pub/irs-pdf/p519.pdf
"nonresident spouse treated as resident" and "how to make the choice"