Households in certain parts of the country are likely to miss out on help to pay their rising water bills thanks to the “postcode lottery” support schemes offered by water companies.

Labour is being called upon to fix the system that allows water companies to determine the generosity of the support they provide to struggling customers.

Consumer groups and charities argue that a single national tariff should be set up to help low income groups with rising water bills, as they warn vulnerable groups are already cutting back on usage due to fears of high charges.

It follows the announcement on Thursday that water companies may be allowed to increase bills by an average of 21 per cent – or £94 – over the next five years to tackle the sewage crisis.

Low income households can request to be put on a ‘social tariff’ if they are struggling to pay their water bill.

However, water companies set the eligibility criteria and some schemes are far more generous than others.

Firms have set out how much support they plan to provide to customers as part their draft five-year business plans, which have been submitted to the regulator Ofwat.

While all plan to increase the level of support available, charities warn this still “falls short of what is needed” given the bill hikes.

In terms of the percentage of customers receiving social tariffs, United Utilities is planning the largest expansion. It plans to provide 15 per cent of customers with a social tariff between 2025 and 2030, compared to 5 per cent in the current five-year cycle.

Yorkshire Water customers are least likely to receive support, with the firm proposing to help 3 per cent of customers, compared to 2 per cent currently.

The level of discount being offered to customers on social tariffs also varies greatly per company.

For example, Thames Water offers 50 per cent discounts on bills, which would mean paying £218 in 2024/25. In comparison, Yorkshire Water currently caps bills at £364.

Many water companies also have other support schemes, including hardship funds and debt support schemes.

How much support does your water company offer?

Eligibility criteria for social tariffs and the level of support available varies depending on your water company.

Here is what the 11 water and wastewater companies in England and Wales offer*:

Anglian Water: Plans to provide 7 per cent of customers with social tariffs in 2025-30. Currently offers up to 50 per cent reduction on annual bills.

Dŵr Cymru: Plans to provide 9 per cent of customers with social tariffs in 2025-30. Social tariff is set at £290.03.

Hafren Dyfrdwy: Plans to provide 6 per cent of customers with social tariffs in 2025-30. Currently offers up to 90 per cent reduction on bills.

Northumbrian Water: Plans to provide 12 per cent of customers with social tariffs in 2025-30. Currently offers up to 50 per cent reduction on bills.

Severn Trent: Plans to provide 9 per cent of customers with social tariffs in 2025-30. Currently offers up to 70 per cent reduction on bills.

Southern Water: Plans to provide 8 per cent of customers with social tariffs in 2025-30. Currently offers up to 90 per cent reduction on bills.

South West Water: Plans to provide 5 per cent of customers with social tariffs in 2025-30. Currently offers up to 80 per cent reduction on bills.

Thames Water: Plans to provide 7 per cent of customers with social tariffs in 2025-30. Currently offers a 50 per cent reduction on bills.

United Utilities: Plans to provide 15 per cent of customers with social tariffs in 2025-30. Caps bills at £282 or £402 depending on circumstances.

Wessex Water: Plans to provide 7 per cent of customers with social tariffs in 2025-30. Currently offers bill reductions of up to £55 per year.

Yorkshire Water: Plans to provide 3 per cent of customers with social tariffs in 2025-30. Currently caps bills at £364.

Social tariffs are primarily funded via the money collected from customer bills. Water companies conduct “willingness-to-pay” research to determine how much their customers are willing to subsidise the tariffs.

Water companies can top this up with money from their shareholders, but only four companies are planning to do this during 2025-30.

They are United Utilities (£69m), Yorkshire Water (£10m), Welsh Water (£0.3m) and SES Water (amount undetermined). Shareholders at other companies have said they will put funding towards other types of support, such as hardship funds.

A spokesperson for Water UK, which represents water companies, said: “Ofwat has now given the green light to companies to triple the level of support for customers. Over the next five years the number of households supported will rise to more than three million.”

Consumer groups and charities have called on the Government to introduce a new national social tariff that water companies must adhere to.

“What’s needed is a fairer and more consistent safety net for households that is more directly linked to people’s level of need,” said Andy White, the senior leader for social policy at the Consumer Council for Water.

Morgan Vine, head of policy at Independent Age, said: “The problem is that every company is different, the eligibility is different, the amount they give you as a discount is different… it shouldn’t be a postcode lottery where older people living on low incomes just have no choice.”

Ms Vine said the charity is “already hearing from people who are cutting back their use now”.

“Any increase, even if it happens over multiple years, is going to really worry people, because they don’t have enough money right now to pay their water bills.

“We’ve heard from people who have told us they’re not doing the washing up, they’re washing less themselves, they’re not doing their laundry often enough… we’ve had people saying they’re not flushing the toilet to try and save water.”

Households with a water meter fitted are charged based on their usage, plus a standing charge. Households without a meter are charged a set amount based on the value of their property.

On Thursday, the regulator Ofwat published its draft decision on water companies’ business plans, which set out how much companies will be allowed to increase bills by and how much they plan to spend over the next five years.

The regulator has made a provisional decision to allow bills to increase by 21 per cent – or £19 per year – between now and 2030 to fund a £88bn investment in England and Wales’ sewerage infrastructure.

The bill increases are a third less than water companies had asked for, with firms proposing bill hikes of up to 73 per cent between 2025 and 2030.

Water companies are under intense pressure to invest in their infrastructure due to public outrage over the amount of sewage flowing into Britain’s lakes, rivers and seas.

Latest annual statistics showed water companies in England spilled untreated waste from thousands of “storm overflow” points 464,056 times in 2023.

Environmental groups accepted that bills would need to increase by some amount to fix the sewage crisis, but blamed Ofwat for not increasing bills more incrementally.

Paul de Zylva, senior sustainability analyst at Friends of the Earth, told i that Ofwat had kept bills too low in recent years, despite being warned about the pollution crisis.

“How much of the current rises reflect a lack of investment in the past because regulators were asleep at the wheel?” he asked.

However, Water UK, the trade association for the industry, argued the bills’ increases were too small to pay for the level of investment needed in England and Wales’ sewerage network.

“For far too long, Ofwat has failed to be realistic about the levels of investment needed and what it will take to deliver and maintain necessary infrastructure,” a spokesperson said.

On Thursday, the Environment Secretary Steve Reed held a meeting with water bosses and set out a number of first steps Labour would take to address the issue, including customer refunds when infrastructure money is not spent on time.

Labour’s manifesto included a number of other pledges to address the crisis, including prosecutions for water bosses and automatic fines for firms, but it is currently unclear when these changes will be introduced.

Mr Reed has warned it will “take time” to improve the state of the country’s rivers, lakes and seas.

A Defra spokesperson said: “We are committed to a water sector that delivers for customers and the environment. Bills must remain affordable and customers cannot be expected to pay the price for years of underperformance in the past.

“We are pushing water companies to ensure support is available for vulnerable customers who are struggling to pay their bills and that their customers know how to access this support if they need help.”