@ankur11 ji, rather than my paraphrasing the requirements ( many items may not be applicable to you though ), I will refer you to "horse's mouth " -- the IRS -->
Departing Alien Clearance (Sailing Permit) | Internal Revenue Service (irs.gov)
Please note depending on the state where you reside, there may also be filing requirements .
Really all have to assure is that all taxes have been collected / withheld.
You still have to file an end of the year return.
A few points to note:
1. You should keep your US bank account operational for perhaps six months or so after filing your final return ( if there is a refund from IRS or from the state these will be US$ denominated checks or direct deposit ( preferrable ).
2. Any interest / dividend earnings once you are a non-resident ( and recognized on form 1040-NR ) will attract a flat 30% federal tax and/or impacted by Tax treaty between US and your tax home country ( India ? )
3. Even when you have left this country, tax on US sourced income ( passive including rental or capital asset disposition ) may attract US and your tax-home country. Therefore one needs to make plans ( disposition or otherwise ) with an eye to future tax implications.
4. You may want to also look in to Social Security / Medicare tax implications --- you paid FICA in the USA and if your tax-home country has a totalization agreement with the USA ( most countries do ).
As a Non-resident , your "Foreign Source " income is generally not taxable in the USA.
Is there more I can do for you ?
Namaste ji
pk
