The free coffee must pay its way: loyalty reward maths for South African SMEs

A free coffee looks small on the menu. Across hundreds of redemptions, it becomes a business decision. Before you promise the tenth cup, work out what you can comfortably give away and what customer behaviour would make the offer worthwhile.

South Africa's August 2026 headline inflation rate was 4.4%, according to Stats SA's release on 23 September. That is context, not your costing sheet. Your beans, cups, milk, card fees and delivery invoices tell you what a reward actually costs. ^[S03]

Start with contribution per sale

Consider a hypothetical Johannesburg café. On a consistent VAT basis, a qualifying coffee sells for R36 and carries R12 in variable costs. It contributes R24 towards fixed costs and profit.

Under buy nine, receive the tenth free, nine paid coffees produce R324 revenue. Variable costs for all ten total R120. That leaves R204 before programme fees, administration, fixed costs and tax.

Without the reward, nine paid coffees would contribute R216. If the reward creates an extra consumption occasion, the direct cost difference is R12. If it replaces a tenth coffee the customer would have purchased anyway, compare R204 with R240 from ten paid coffees. The difference is R36. Behaviour changes the answer.

Compare rewards on the same basis

A 5% future credit on R324 creates R16.20 in reward value. That is not automatically R16.20 of product cost, nor does it guarantee another purchase. Model redemption, eligible products and additional spending. Do not call restricted store credit cash that customers can withdraw.

Truth and BrandMapp's 2025/6 research identifies cashback as a strong stated preference among its surveyed consumer groups. Preference helps you design an understandable offer, but it does not settle which structure pays for your shop. ^[S05]

Another option is an extra item with a qualifying basket. A bakery might offer a defined product with a purchase above a threshold, provided the extra basket contribution funds it. Keep the rule short enough for a cashier to explain while the queue is moving.

Set a limit before you launch

List software, messaging, staff time and expected reward costs separately. If these total a hypothetical R1200 a month and each genuinely additional paid visit contributes R24 after its own variable costs, you need 50 extra visits to cover that budget. Include rewards only once in the calculation.

Run one offer for a defined period. Track redemptions, repeat visits and contribution, then compare with an appropriate baseline or untreated group. A growing stamp count is encouraging; it is not yet a profit calculation.

Futhi advertises punch cards, cashback and points, giving you several structures to discuss. ^[F02] Bring your actual costs and normal buying pattern to the conversation. Your till can be generous. It still needs to balance.