Various tillage systems (including conventional and top-layer practices) were identified and financially analysed by determining income and cost effects of the systems. Net margin analyses provided illuminating rank-order shifts. The rip-on-row methods are the most economic tillage systems in the North-Western Free State. The best three systems (all top-layer systems) performed on average 111 % better than the conventional systems in respect of net margin per R100 of capital invested.