Beyond the Tax : A Field Experiment on Consumer Behaviour Following the Abolition of the Swedish Plastic Bag Tax

Sammanfattning

This paper tests whether nudges can serve as a low-cost policy tool after the abolition of the Swedish plastic bag tax in November 2024. From a supply and demand perspective, the removed tax should increase consumption, yet the post-tax context may still be shaped by habits, norms, and reference points formed during the tax period. This creates a clear policy question: can nudges influence behaviour in the gap left by a removed price instrument? To examine this, a randomised field experiment was conducted in a Swedish supermarket. Customers at three checkout types were exposed to either an informational nudge, a moral nudge, or no intervention, and their plastic bag purchases were recorded. Neither nudge had a statistically significant effect on purchase probability. The conclusion is clear: in this setting, low-intensity informational and moral nudges do not work as substitutes for the abolished tax.