What is the maximum validity for H-1B1 visas (for Singaporeans)?

The H-1B1 is the specialty occupation category created by the U.S.-Singapore Free Trade Agreement for citizens of Singapore. Two separate time limits apply to it, and they are easily confused: how long the visa itself can be used, and how long the holder may stay in the United States on each admission.

Visa validity. Under the Department of State reciprocity schedule for Singapore, an H-1B1 visa is issued for a maximum of 18 months, for multiple entries, with no reciprocity (issuance) fee. That 18-month figure is the outer limit of the visa's usefulness for travel: it sets how long the visa may be presented at a port of entry to request admission. It is not a period of permitted stay, and it says nothing about how long the underlying employment may last.

Authorized stay. Admission in H-1B1 status is granted for up to one year at a time, and extensions are granted in further one-year increments under INA 214(g)(8)(C). The Form I-94 admission record, not the visa foil, controls how long the person may remain. Each period must be supported by a labor condition application certified by the Department of Labor (Form ETA-9035E) covering the offered employment.

Renewals. Nothing in the H-1B1 provisions sets a fixed lifetime maximum, so the status can in principle be renewed year by year for as long as the qualifying employment and the temporary intent behind it continue. H-1B1 is not petition-based: a new visa is applied for directly at a U.S. consular post abroad. To extend the stay without departing, the employer files Form I-129 with USCIS under 8 CFR 214.1(c)(1). Repeated renewals attract closer scrutiny of nonimmigrant intent.