Can I Stay in U.S. Longer with My Non-immigrant Visa?

Question,

I have a non-immigrant visa. What will happen if I decide to stay in U.S. longer beyond the period of time authorized in the visa? Does that mean I will be out-of-status?

Answer,

With a non-immigrant visa, you should carefully consider the dates of your authorized stay, and make sure you are following the procedures. Failure to do so will cause you to be out-of-status. Staying beyond the period of time authorized by the Department of Homeland Security and out-of-status in the U.S. is a violation of U.S. immigration laws, and may cause you to be ineligible for a visa in the future for return travel to the U.S. 

If you overstay the end date of your authorized stay, as provided by the CBP officer (U.S. Customs and Border Protection) at a port-of-entry, or United States Citizenship and Immigration Services (USCIS), your visa will be automatically voided or cancelled.

http://www.greencardapply.com/question/question16/Non-immigrant_Visa_121116.htm 

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