Social security plays an essential role in an economy, but if designed incorrectly, it can distort individuals' labour supply and savings behaviour. We explore how well the Australian means‐tested pension system provides social insurance by changing the settings of the system and calculating the impact on welfare. In order to exclude trivial welfare gains, we keep the cost of the programmes constant. We find that the means‐tested pension system is welfare reducing, but does provide a better outcome than a PAYG system of equivalent cost. We also find that if the benefit amount is held constant, and hence the cost of the pension programme is allowed to vary, a taper rate of 1.0 is optimal. However, once we hold the cost of the programme constant, a universal benefit scheme provides the best welfare outcome.