22 C.F.R. 41.112(d)-An alien can re-enter the U.S. with an expired visa in her passport if:
In essence, Automatic Revalidation may allow you to reenter the U.S. after a brief trip to Canada or Mexico without going to the Consulate for a new visa. How do you qualify for Automatic Revalidation?
If your nonimmigrant visa is expired and you must travel to Canada or Mexico for less than 30 days, automatic revalidation may apply to you.
Automatic Revalidation applies when:
Automatic Revalidation may also apply when you have changed status in the U.S. and never had the new visa stamped in your passport or the visa is now expired.
For example: An Indian citizen on L-1B visa is working in the United States. He applies for and is approved for an Extension of Stay and receives an Approval Notice which includes a new I-94 at the bottom. The L-1B employee is asked to go to Canada for business meetings for a two week period. There is no Consular appointment available to have the extended visa stamped in his passport. He returns through the Border (or Airport preinspection station), shows his unexpired passport, expired visa and Approval Notice and requests Automatic Revalidation to return to the U.S. Under Automatic Revalidation, the Officer can allow the L-1B employee to enter without a new stamped visa in the passport. CAUTION: While Automatic Revalidation is authorized, several Ports of Entry will not admit a nonimmigrant based on Automatic Revalidation. Therefore, it is best to contact the Port of Entry to confirm local policy before you attempt to enter via Automatic Revalidation.