What Is ROI?
Return on Investment (ROI) is a profitability metric that calculates how much profit you generate relative to the total cost of an investment. The formula is simple: subtract your total investment cost from your net profit, divide by the investment cost, and multiply by 100 to express it as a percentage. A marketing campaign that costs R50,000 and generates R200,000 in profit has an ROI of 300%.
Unlike ROAS, which only measures revenue against ad spend, ROI is a true profitability measure that accounts for all costs associated with a campaign or business activity. This includes agency management fees, creative production costs, staff time, platform fees, and the cost of goods sold. ROI gives a more realistic picture of whether a marketing investment is actually making your South African business more profitable.
Marketing ROI is notoriously difficult to calculate perfectly because of attribution challenges how do you assign credit for a sale that involved a Google Search click, three remarketing impressions, and a WhatsApp message? Most South African businesses use a combination of last-click attribution and multi-touch models, accepting that some level of estimation is inherent in the process.
Why ROI Matters for Your Business
ROI is the ultimate justification for any marketing expenditure. Board members, shareholders, and business owners need to see that marketing spend is generating more value than it costs not just in revenue, but in profit after all expenses are accounted for. Reporting ROI rather than vanity metrics like impressions or follower counts demonstrates that marketing is a growth investment, not a cost centre.
Calculating ROI by channel helps South African CMOs and business owners allocate budgets rationally. If SEO delivers 400% ROI and display advertising delivers 80% ROI, the budget allocation decision becomes data-driven rather than based on industry trends or salespeople's pitches.
FAQ
What is a good ROI for digital marketing in South Africa?
A good digital marketing ROI in South Africa is 300% or higher, meaning you earn R3 in profit for every R1 invested. Professional services firms with high margins can be profitable at 200% ROI, while e-commerce businesses with lower margins should target 300% to 500%.
How is ROI different from ROAS?
ROI accounts for all costs including agency fees, staff, tools, and production costs, measuring true profitability. ROAS only measures revenue against ad spend. A campaign can show a healthy 5x ROAS but have a lower ROI once all operating costs are factored in.