After being released by AFC Fylde after their relegation to National League North, Hereford boss Paul Caddis managed to get Richardson to sign for the Bulls on a permanent basis.
After the signing was announced, 26-year-old Richardson said he was "buzzing to be back".
He added: "A huge club with unbelievable fans and a manager I love playing under. A place I felt at home from minute one, so it was only right to make it my permanent home. Time for a special season #UTB."
Richardson made 23 appearances for the Bulls last season after joining on loan from Fylde.