The 35-year-old spent the last four seasons with the Washington Nationals and hit .259 with an .340 on-base percentage, 26 home runs and 92 RBI in 2014. Near the end of the regular season, LaRoche said he didn't expect to be brought back by the Nationals.
The Miami Marlins were also interested in the free agent and reportedly made a two-year, $20 million contract offer to LaRoche earlier in the week.
LaRoche has played with five different teams over his 11-year career and has a .264 career average with 243 home runs and 838 RBI.
In 2012, the first baseman won both a Gold Glove and Silver Slugger Award. He came in sixth place in the NL MVP voting after hitting .271 with 33 home runs and 100 RBI.
LaRoche is a former 29th-round draft pick by the Atlanta Braves in 2000.
The White Sox finished 73-89 in 2014 and came in fourth place in the AL Central.
- Molly Geary