Transitioning from F-1 OPT to H1B is the most common path for international students working in the US. Here is the complete timeline and strategy: **Standard OPT Timeline:** - 12-month OPT: Start after graduation, must apply 60 days before completion - STEM OPT Extension: 24 additional months for STEM degree holders at E-Verify employers - H1B lottery registration: March of each year (register ASAP on day 1) - Cap-gap coverage: If your OPT expires April–September and your H1B is pending, cap-gap covers you **Cap-Gap Rule:** If your OPT (or STEM OPT) expires between April 1 and September 30, and your H1B petition is timely filed, cap-gap automatically extends your OPT status and work authorization until September 30 or until USCIS decides your case. **What to do if not selected in lottery:** Apply for STEM OPT extension immediately if eligible. Consider cap-exempt employers (universities, research labs, nonprofits). Explore L-1, O-1A, or EB-1A pathways. Some employers transfer employees to Canada or Europe, then use L-1 to return to the US. **Critical mistake to avoid:** Never let your OPT EAD expire while waiting for the H1B result. Maintain continuous authorized status.