AXA Winterthur is a multinational insurance company. The original company named Winterthur was founded in Winterthur, Switzerland, in 1875.

Winterthur has subsidiaries in Germany, the United Kingdom, Belgium, the Netherlands, Hungary, Poland, the Czech Republic, the United States, Slovakia, Japan, Taiwan, Hong Kong, and Luxembourg. In addition, it has subsidiaries in Spain, although AXA are based in Madrid and Winterthur are based in Barcelona.