On March 5, USCIS announced that all Forms I-129 (Petition for Nonimmigrant Worker, including H1B) and I-539 (Application to Change/Extend Nonimmigrant Status, including H1B Extension) should be filed to Vermont Service Center (VSC) or California Service Center (CSC), effective from April 2, 2007. On March 9, 2007, USCIS announced the new direct filing addresses based on the states of application. The following is the filing chart.

California Service Center (CSC)
Covers the following states:

Alaska, Arizona, California, Colorado, Guam, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Montana, Nebraska, Nevada, North Dakota, Ohio, Oregon, South Dakota, Utah, Washington, Wisconsin or Wyoming.

Mailing address:

USCIS
California Service Center
ATTN: H-1B Cap (or H-1B U.S. Masters Cap)
P.O. Box 10129
Laguna Niguel, CA 92607-1012

Mailing address for Premium Processing Service

Premium Processing Service
USCIS
California Service Center
ATTN: H-1B Cap (or H-1B U.S. Masters Cap)
P.O. Box 10825
Laguna Niguel, CA 92607

Vermont Service Center (VSC)
Covers the following states:

Alabama, Arkansas, Connecticut, Delaware, the District of Columbia,Florida, Georgia, Kentucky, Louisiana, Maine, Maryland, Massachusetts,Mississippi, New Hampshire,New Jersey, New Mexico, New York,North Carolina, Oklahoma, Pennsylvania, Puerto Rico, Rhode Island, South Carolina, Tennessee, Texas, Vermont, Virginia, U.S. Virgin Islands, or West Virginia.

Mailing Address:

USCIS
Vermont Service Center
ATTN: H-1B Cap (or H-1B U.S. Masters Cap)
1A Lemnah Drive
St. Albans. VT 05479-0001

Mailing Address for Premium Processing Service

Premium Processing Service
USCIS
Vermont Service Center
ATTN: H-1B Cap (or H-1B U.S. Masters Cap)
30 Houghton Street
St. Albans. VT 05478-2399

Please Note:
The service center for H-1B applications is determined by the address of the employer, but for H-1B extension applications, it is determined by the address of the beneficiary (individuals).

Please make sure your application is sent to the right service center, otherwise, you may miss H-1B quotas should your application is delayed.