Midfielder Richards surprisingly finds himself heading out of the exit door at the Greenhous Meadow having made 43 appearances this season, scoring seven goals in the process.
He tops Town's scoring chart this term alongside striker Marvin Morgan, who has also been released by boss Graham Turner as he wastes little time shaping his squad for next season after Town avoided relegation from League One.
The pair depart along with midfielders Mark Wright and Rob Purdie as well as striker Ryan Doble.
Meanwhile, Turner has offered contracts to six players also out of contract at the the Shropshire club.
It is hoped Jon Taylor, Aaron Wildig, Connor Goldson, Jermaine Grandison, Tom Bradshaw and Ryan Woods will each accept the terms on the table.