The budget carrier will operate a new Exeter-Faro route four times a week, while Stansted will gain a new three-times-weekly Leipzig route.
A new four-times-weekly Belfast route, meanwhile, will take off from Cardiff in the spring.
Ryanair will operate 26 weekly flights to/from Cardiff this summer, including 14 to/from Dublin and four each to/from Faro and Malaga.
Exeter will have 12 weekly flights – four each to/from Alicante, Faro and Malaga.