CHICAGO--(BUSINESS WIRE)--Fitch Ratings has assigned a 'B+' rating to Wintrust Financial Corp.'s (WTFC) $125 million series D non-cumulative perpetual preferred stock issuance. Dividends will be payable at a fixed rate of 6.50% per annum from the original issue date to, but excluding, July 15 , 2025 and thereafter at a floating rate of three-month LIBOR plus a spread of 4.06% per annum. The proceeds will be used for general corporate purposes, which may include, investments at the holding compa