Please help...

I was on my OPT from Nov. 2004 to Nov. 2005.
Started working from June 2005
My H1B started on Oct. 2005

Am I a Resident or Non-resident for tax purposes??

Would be really glad to know,. thank you!

You are non resident as your H1B starts from October 2005. Even though, you just need to file your taxes using 1040

I disagree with Vatlam.

While you could probably file Form 1040 and the IRS would not notice, legally you should file Form 1040NR ONE LAST TIME. You asl need to file Form 8843.

If you have some over-riding reason to need to file as a resident alien, you can do so legally if you wait until June to file. That way, you qualify as a resident alien under the Substantial Presence Test. This option is called First Year Choice.