Some entry-level plans charge less for low-income earners and progressively more as your income rises. This makes private healthcare accessible to people earning under R20,000/month who couldn't otherwise afford a scheme. You declare your gross income at enrolment and at every annual renewal; moving between bands changes your monthly contribution but not your benefits.
SA example: Discovery KeyCare Plus costs R1,961/month if you earn under R10,250, but R3,980/month if you earn over R16,600. Same plan, same benefits, different price. Momentum Ingwe, GEMS, BonCap and Bestmed Rhythm work the same way.