The Liberal Democrats have introduced a proposal requiring supermarkets to disclose instances of 'shrinkflation', where the quantity of pre-packaged products decreases while prices increase.

This amendment to the Product Regulation and Metrology Bill mandates that large supermarkets display any changes in product quantity alongside the increased unit price for a period of 60 days.

Lib Dem trade spokesman Clive Jones highlighted the importance of transparency in pricing, especially during the ongoing cost-of-living crisis, to protect consumers from being misled.

The aim of this proposal is to ensure customers are aware if they are paying more for less, particularly in light of current economic pressures.

Research from 2024 by Compare the Market has shown that common products like digestive biscuits, butter, crisps, and chocolate bars have shrunk in size while their prices have risen.

Jones emphasized that large companies and supermarkets should be held accountable for their pricing practices that unfairly burden shoppers.

In addition to this proposal, the Government has committed to introducing stricter labeling laws in 2026 to enhance price clarity for consumers, ensuring unit prices are clearly displayed in kilograms or liters.

The Bill also includes provisions for regulating the marketing and use of goods in the UK post-Brexit, previously amended to protect the imperial pint measure.

Members of Parliament are expected to vote on this proposal on June 4, 2025, during the report stage of the Bill in the House of Commons.

If passed, this legislation would require supermarkets to inform customers whenever they are experiencing shrinkflation.

The proposed changes aim to empower UK ministers with the authority to regulate goods marketing and usage in the post-Brexit landscape.

The government's forthcoming laws aim to improve pricing clarity, which aligns with the Liberal Democrats' push for transparency in supermarket pricing.