One of the best paying referral programs is SurveySavvy. They offer repeat commissions.
SurveySavvy gives you $2 repeated commissions for each referral over time. While your raking in that passive income, you can be doing surveys too for $3 a pop.
When your own referral also refers someone, they get $2 bucks and you get a $1 for that too.
SurveySavvy is an internationally offered service, giving you a much wider web to cast out when you are hunting for referrals.
Also their app SurveyConnect pays five dollars if you install it from U.S.A.