On 1 January 2018, the municipality of Amsterdam changed the system for the reception of unaddressed mail from presumed consent to explicit consent to reduce paper waste. This policy can be defined as a default nudge. The no-choice population received unaddressed mail in the presumed consent system but not in the new explicit consent system. Residents receive unaddressed mail only when they actively decide to put an opt-in sticker on their mailbox. This study assesses the effectiveness and social benefits of this nudge.
According to research from VU University in Amsterdam, the effect on paper waste is estimated using a difference-in-differences approach in which several other Dutch municipalities function as the control group. The main finding is that the default nudge reduces paper waste between 5.3% and 11%. Social benefits of this reduction include, for example, lower carbon emissions for collecting and transporting paper waste, equivalent to yearly benefits between €135,000 and €285,000 in Amsterdam.
If all Dutch municipalities implement the system of explicit consent for unaddressed mail, the yearly benefits are approximately between €14 million and €30 million. The default nudge is a low-cost policy to implement and offers municipal policymakers a cost-effective way to reduce waste.