The three players had brilliant seasons for Northampton and were central to the team’s promotion push, which fell agonisingly short on the final day of the campaign.
Roberts started every league game of the regular season and kept more clean sheets than any other goalkeeper in the country, while Horsfall captained the team in the absence of Joseph Mills and homegrown midfielder Shaun McWilliams had his best campaign in terms of games played, racking up 43 appearances in all competitions.
The club have been in talks with all three players for several months but are yet to reach an agreement and there is almost certain to be interest from elsewhere given their performances.
Brady said: "We had an excellent season but whatever the circumstances, we fell short by the narrowest of margins. With that in mind, we need to create room in the squad to try and improve and take that next step.
“As we did last summer, we will undergo a thorough recruitment process again and we have already started meeting with players and agents ahead of the new season."