An innovative tariff trial led by Affinity Water is showing strong early results in reducing customer bills and cutting water usage, a dual win for households and the environment.

The WaterSave Tariff trial, launched in October 2023 in Stevenage, introduced a rising block pricing structure to 1,337 properties. Under this model, customers pay more per litre as their usage increases, encouraging conservation while keeping water affordable.

The first block of water, which covers a household’s basic needs, is free of charge, ensuring that low-use households are not financially burdened. This strategic approach aims to balance affordability with sustainability.

Early data shows that around 75% of customers in the trial are paying less for their water compared to the standard tariff, with a median bill saving of 20%. For many single-occupancy households, water bills have nearly halved. Even among typical four-person households, bills were on average 10% lower.

Alongside the financial benefits, water use has declined by an average of 12 litres per person per day. Compared to a control group, households in the trial used nearly 10,000 litres less per property annually. These savings, while modest per home, have the potential to scale significantly.

The trial also had a notable impact on affordability. Customers in the trial group cleared arrears faster and more consistently than those in the control group, with arrears falling by 25% - compared to just 9% elsewhere. Within a single month, 70% of previously indebted trial customers were back on track, suggesting a meaningful link between the new tariff and financial resilience.

Martin Hall, Head of Economic Regulation at Affinity Water, said:

“Our trial is a clear example of how we can use smart, fair pricing to drive real change. We’ve shown that it’s possible to reduce consumption without penalising those who need support, in fact, we’re seeing lower bills and improved affordability for most customers. The early results are very encouraging, and we’re excited about the potential for wider rollout.”

Looking ahead, Affinity Water is exploring an expansion of the WaterSave Tariff to up to 120,000 customers. If scaled across all of its one million metered households, it could reduce water demand by up to 26 million litres per day, equivalent to the daily usage of more than 170,000 people. Financially, the reduction in arrears across the full customer base could total £4.7 million annually.

As the region faces growing pressures on water resources, Affinity Water sees smart tariffs as part of a long-term strategy to ensure fair, affordable, and sustainable access to clean water.

Water Minister Emma Hardy commented:  

“This promising trial from Affinity Water is exactly the sort of innovation we want to see more of across the water industry. I welcome the forward-thinking approach and the strong early results, because what really matters is improved services for customers, a better environment and pounds back in people’s pockets.”

Affinity Water will continue to evaluate the trial and engage with customers, regulators, and stakeholders as it considers next steps.