A foreign national may remain in H status for a maximum of six years.  Time spent in H category is deducted from the available H-1B period of stay, unless the foreign national has been physically absent from the U.S. for at least 12 months.

An extension should be filed before the expiration date of the foreign national’s current H-1B status, but no more than six months before the current H-1B status expires.

The procedure for obtaining an extension is similar to those followed to obtaining the initial H-1B status.  

A foreign national for whom the employer has filed a timely application for an extension, can continue employment for the same employer while the request for extension of stay is pending with US Citizenship and Immigration Services for a period of up to 240 days beyond the expiration of the prior period of stay.

To take advantage of this rule, the following conditions must be met:

• The application must be received by USCIS in a “timely” fashion and before  the expiration of the current period of the H-1B status.
• The H-1B foreign national continues to work only for the same employer that has filed the extension.