When should I tell a guy I’m not interested in dating him?

During hang out or after hang out? Been seeing him for over 3 months
Updates
11 mo
Hey , I did end up telling him, and we did leave off on good terms. Thank you for the help!
Updates
11 mo
Any person that writes answers that are belittling my decision are getting automatically deleted. Do not waste your time especially because this issue has already been solved and me and this guy are FINE and are civil. Do not come here to project your own rejection insecurities
When should I tell a guy I’m not interested in dating him?
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