Commentary: Supermarket plastic bag charge – a case where policies work but expectations diverge

In contrast, jurisdictions like Ireland treat the charge as a levy, with proceeds channelled into a central environmental fund. That structure provides clarity, but it also frames the charge explicitly as a form of taxation which is a move that may not be politically or contextually suitable everywhere.

If Singapore were to look to other jurisdictions for lessons, one implication is that pricing measures tend to be more effective when applied consistently across comparable retail contexts.

For instance, having plastic bag charges applied broadly across retail outlets reinforces a clear deterrent signal. On the other hand, applying them to a narrower segment of retailers may raise questions about proportionality and effectiveness, particularly if similar plastic usage continues elsewhere without equivalent signals.

All in, the plastic bag charge is a useful policy tool, and evidence suggests it has nudged consumers to be more prudent in using disposable bags. But it also offers a reminder that sustainability policies need to be designed and communicated beyond compliance, especially when consumers are asked to repeatedly adjust their habits or absorb small costs. 

When public expectations drift apart, even effective policies can feel misaligned.

Heng Li Seng is founder of social enterprise Green Nudge.