Wis. Stat. § 76.66: Retaliatory taxation of nondomestic insurers.

(1) In this section, “taxes” means the taxes imposed on nondomestic insurers under ss. 76.60, 76.63, 76.65 (2) and 601.93 less offsets allowed against those taxes under s. 646.51 (7) or the amounts imposed on domestic insurers by another state or foreign country for similar purposes.

(2) If another state or foreign country requires a domestic insurer doing business in that state or country to pay taxes greater in the aggregate than the aggregate amount of taxes that a nondomestic insurer doing business in this state would pay, each insurer domiciled in that state or foreign country shall pay to this state for the same year the amount that a domestic insurer doing a similar business would be required to pay to the other state or foreign country.