Richardson had spent time on loan at Hereford, joining in early January and staying at Edgar Street until the end of the National League North season.
He impressed during his time with the Bulls, where he made 23 appearances, though he was now one of nine players released by full-time Fylde.
A signing of intent from the Hereford boss.
After the final day of the season, Richardson posted on Instagram: "The last four months at this fantastic club have been some of my most enjoyable in football. I’ve loved every moment of being a Bull and just want to say a huge thank you to the fans and everyone at the club for making me feel welcome and valued from minute one.
"Sorry we couldn’t end it in the best way, but the support you have shown us all has been unbelievable and I’m sure it won’t be long until the club is back where it belongs!"