Changing employers on H1B is called an H1B transfer. It is one of the most common H1B actions — here is the complete process.
**H1B portability (AC-21):** Under the American Competitiveness in the 21st Century Act (AC-21), you can start working for a new H1B employer as soon as they file a non-frivolous H1B petition, provided: (1) you have had H1B status for 180+ days since the initial approval, (2) the new petition is filed before your current H1B expires, and (3) the new position is in the same or similar occupational classification.
**The transfer process:** 1. Get a job offer from new employer 2. New employer files I-129 petition with USCIS (and optionally Form I-907 for premium processing) 3. Once USCIS receives the petition (not approves — just receives), you can start working 4. Your old employer does NOT need to be notified and cannot stop the transfer 5. Inform your old employer only after you have decided to leave — they may revoke your H1B, but this does not affect portability if you are already working for the new employer
**Do you need premium processing for a transfer?** Not required, but recommended if: you need certainty before your current H1B expires, your OPT or other status is running out, or the new employer needs confirmation quickly. Premium processing ($2,805) guarantees a 15-business-day response.
**If the transfer petition is denied:** If USCIS denies the H1B transfer after you have already started working for the new employer under portability, your status becomes unlawful from the denial date. File an appeal (Motion to Reopen/Reconsider) immediately and consult an immigration attorney. You may need to file a new petition.
**Multiple H1B transfers:** There is no limit to how many times you can transfer H1B. Each transfer requires a new I-129 petition. Your H1B validity remains tied to the original cap approval and can be extended in 3-year increments.