We examine the bunching behaviour of individuals in Australia in response to an extra 15 per cent tax on compulsory retirement contributions imposed on those earning more than $250,000. We find almost no bunching by wage and salary earners. There is extensive bunching by those with business or trust income. For this group, we estimate an elasticity of taxable income of 0.032. Females and older workers are more likely to bunch. The results suggest that the tax induces a substantial tax planning response but little labour supply response.