The voluntary sector title will launch a new 80-page monthly magazine, with an iPad edition being released later in the summer.
The changes in Third Sector are in response to research conducted into the formats and content that readers prefer, says Haymarket. The research revealed high usage of tablets and smartphones among readers, who have a strong interest in more in-depth articles in a monthly print edition.
Stephen Cook, editor of Third Sector, said: "Third Sector has been providing the best coverage of charities and the voluntary sector for more than 20 years, and we update it regularly to keep pace with what our readers require.
"The new monthly version is an exciting departure, combining more analysis, comment and longer interviews with extended updates and new sections on people, good practice and careers. Meanwhile the weekly iPad edition and new-look website will keep readers fully up to date."
The last weekly edition was published on 10 June.
