The number of older adults using e-commerce platform has grown rapidly in recent years. This has created a whole lot of challenges and research problems in the field of adapting e-commerce systems and algorithms to the needs of older adults. In the current study We have conducted an experiment involving 60 older adults whose task was to participate in realistically modeled Dutch auctions. Results show that more advanced age has a clear, statistically significant adverse impact on the overall performance in Dutch auctions, and that need for cognitive closure is correlated with decreased performance in auctions.