About 10-11 years. Congress allocates 23,400 immigrant visas a year in the F3 category (married sons and daughters of U.S. citizens). For years, the number of petitions far exceeds the number of available visas; hence the backlog. In October 2012, immigrant visas will be issued to the benficiaries of the petitions that were filed in May 2002.
Answered on Sep 22nd, 2012 at 10:45 PM