The BMW X3 fueled the increase with a 156 percent boost in global sales last year to 117,944 vehicles. BMW sold 27,793 of its redesigned X3s in the United States last year compared with 6,075 X3s in 2010.
BMW said 70 percent of the vehicles made in Spartanburg are exported.
The German automaker held a ceremony today to mark production of the 2 millionth vehicle at the plant, which opened in 1994. BMW said the latest expansion will bring its total investment there to nearly $6 billion.
Automotive News Europe and Reuters contributed to this report.