US Visa Singapore

F2 family visas are for spouses and children, and unmarried sons and daughters of permanent residents.  There is an annual quote of 114,200 visas available plus the number (if any) by which the worldwide family preference level exceeds 226,000, plus any unused first preference (F1) numbers.

F2A family visa category is specifically for spouses and children of permanent residents and receives 77% of the overall second preference (F2) limitation, of which 75% are exempt from the per-country limit.

The US State Department maintain an updated monthly list of the wait times for family visa applications.  The monthly list of wait times is called the "Visa Bulletin" and can be found on the US Department of State website.  The Visa Bulletin will show various dates under each family visa category (F1 - F4).  The date listed therein is the date in which the applications they are currently processing were filed.
 
Please  note that once you apply for a F2A family visa that such applicant would not qualify for a tourist, business or student visa because such visas require an intent "not" to immigrate to the US.  By filing the F2A family visa application you are declaring you have an intent to immigrate to the US and such makes you ineligible to receive a "temporary non-immigrant visa" such as tourist, business or students visas.

F2A family visas allow the holder to receive a US green card.  However, the wait for F2A family visas to become available takes many years (3+).  Thus, the F2A family visa is only an option for applicants who do not need to travel to the US in the near future.