That being said, the first major phase of the process involves the submission of petitions to USCIS. As many petitions are filed with USCIS each year, this phase of the process is often the most time consuming as the US Citizen or Lawful Permanent Resident’s petition must wait in the queue for adjudication.

Recently, USCIS updated their processing time estimates, below please find the most recent processing time estimates for family based petitions for K-1 visas, K-3 visas, and Immigrant visas.

The California Service Center processing times are as follows:

The Vermont Service Center processing times are as follows:

One should not misunderstand the above information, these processing times do not reflect the entire time that it takes to complete the entire visa process as a US Family visa petition must also process through the National Visa Center as well as the Embassy in the country where the visa is to be issued. In Thailand, most visa applications for family members of US Citizens or Lawful Permanent Residents are adjudicated at the US Embassy in Bangkok.

The following are the processing times for the USCIS California Service Center as of September 30, 2009:

The following are the processing times for the USCIS Vermont Service Center as of September 30, 2009:

It should be noted that these processing times are only estimates and every Immigration petition is unique in that it processes at its own pace. Further, these processing times are only relevant with regard to USCIS. The US Embassy in Bangkok and the US Consulate in Chiang Mai process applications after they have received USCIS pre-approval.