Generally, you must leave the U.S. by the date indicated on your Form I-94 (not necessarily the date on the visa stamp itself). However, you can legally stay in the U.S. after your visa expires if you have a pending application for an extension or a change of status. If you file Form I-539 (Application to Extend/Change Nonimmigrant Status) before your authorized stay expires, you are generally permitted to remain in the country while the U.S. Citizenship and Immigration Services (USCIS) reviews your case. During this "pending" period, you do not accrue "unlawful presence." Another option is if you qualify for an Adjustment of Status (such as through marriage to a U.S. citizen), which allows you to stay while your green card application is processed. It is vital to note that simply "staying" without a filed application is a violation of federal law and can result in a 3-year or 10-year bar from re-entering the U.S. if you overstay by more than 180 days. In 2026, USCIS systems are highly automated, and overstays are tracked electronically, so always ensure you have a "Receipt Notice" for a pending case to prove your legal right to remain.