Twice-weekly flights to the Latvian capital, a burgeoning city break destination, will get under way on 18 October.
Flights will operate on Wednesdays and Sundays.
The addition comes as Wizz prepares to base a second Airbus A320 in Riga.
Other new Riga routes include Bergen, Billund, Hamburg, Reykjavik, Stockholm, Trondheim and Tallinn.
Wizz chief commercial officer George Michalopoulos said the move was the ideal way to mark 10 years’ operations in Riga.
Birmingham fares will lead in from £21.99pp one-way.