The effective enforcement of traffic laws is critical for improved road safety outcomes. Decisions to follow traffic rules and pay fines are influenced by formal institutions (e.g. laws, court summons, and fines) as well as informal institutions (e.g. norms and aspects of culture). Formal and informal institutions create incentives that should be designed to steer individuals’ behaviour towards desired outcomes. Unfortunately, there is no reason to believe that the institutions to deal with traffic violations in South Africa currently create effective incentives. This paper discusses the findings of a controlled laboratory experiment, conducted with a sample of university students, that tested the efficacy of different financial incentives that may influence the payment of traffic fines. An early payment discount was compared to a late payment penalty (used in other countries, for example, some states in the USA), and to the absence of any incentives. Furthermore, we examined whether the willingness to settle fines is sensitive to the likelihood of detection by the authorities. We found that introducing financial incentives significantly increases voluntary payment of fines, irrespective of whether immediate payment is encouraged with a discount or late payment is discouraged with a surcharge. In addition, subjects are more sensitive to the likelihood of detection when financial incentives are present.