As of 2015, there are four former presidents of the United States still living: Jimmy Carter, George Bush, Bill Clinton and George W. Bush. George Bush is the oldest of the four.
Jimmy Carter was born in 1924 and served as president for one term from 1977 to 1981. George Bush was born in 1924 and served one term as president from 1989 to 1993. Bill Clinton was born in 1946 and served two terms as president from 1993 to 2001. George W. Bush was born in 1946 and served two terms as president from 2001 to 2009. The current president of the United States is Barack Obama. He began his first term as president in 2009 and was elected to a second term in office in 2012.