Honest ROI requires a clear understanding of your full loyalty program economics, not just the visible costs. If program costs are not clearly defined, ROI becomes a debate instead of a reliable metric. Redemption cost is often the largest and most complex input because it must be estimated, as issued rewards do not equal redeemed rewards. If you do not yet have a clean loyalty P&L, start with a minimum viable denominator, typically redemption cost, and expand over time with a transparent, documented plan.
“Loyalty program cost” should mean: the costs required to operate the program and deliver rewards/benefits over a defined time horizon.
Avoid the double-subtraction trap and be explicit about the metric you are presenting
Be explicit about what metric you’re presenting:
Incremental profit before program costs (sometimes called “gross incremental profit”): the profit uplift attributable to loyalty before subtracting loyalty program costs.
Net incremental profit: incremental profit before program costs minus program costs.
ROI (net over cost): ROI = (net incremental profit) ÷ (program cost)
Benefit–cost ratio: (incremental profit before program costs) ÷ (program cost)
Correct Loyalty Program ROI Formula: (net incremental profit) ÷ (cost) = (incremental before costs − cost) ÷ (cost)
Incorrect (double subtract): (net incremental profit − cost) ÷ (cost)
The double-subtraction trap happens when someone uses net incremental profit as the numerator and then subtracts program costs again (implicitly treating the numerator as if it were “before costs”).
In other words:
If you don’t have a clean loyalty P&L, a finance-safe first step is:
If you assume issued points will cost $1.0M to redeem but true redemption cost is$1.4M (because behavior changed), your ROI can flip sign months later. This isn’t just an accounting nuance, errors accumulate over time.