• New research by Nesta finds almost 8 million households across the UK are each missing out on £57 by not tweaking the flow temperature of their combi boiler.
• When combined with Nesta’s package of six free energy-saving measures, including turning down boiler flow temperature, the average household can save £220 on their energy bills.
• As the clocks go back and the heating goes on, Nesta is urging households to use just five minutes from the extra hour to visit its online tool and take six easy actions for a cheaper winter via https://moneysavingboilerchallenge.com/

London - Almost 8 million UK households are missing out on an opportunity to shave almost £60 off their energy bill by tweaking the flow temperature of their combi boiler, according to new research from Nesta, the research and innovation foundation.

Nesta is sharing advice to help people save £57 on their bills - and offset the £60 October price cap rise as temperatures begin to drop after an unusually warm start to autumn.

These savings can increase from £57 to £220 by incorporating Nesta’s six free money-saving measures. The foundation is urging consumers to take part in its Money Saving Boiler Challenge and visit its online tool - https://moneysavingboilerchallenge.com/ - to learn how to save money this winter.

Lowering the flow temperature (the temperature of water as it enters a radiator) on a combi boiler to 60°C or below allows the boiler to recover and reuse heat that would otherwise be wasted through the flue.

Nesta commissioned Cambridge Architectural Research to compare various energy saving measures that households can take this winter. It suggests that 26% of all UK homes (7.5 million) can make this change to save £57 a year.

The analysis also found that combining six free and simple adjustments can save households just over a quarter (28%) of their annual energy bill, slashing their costs by £220 a year:

• Reduce flow temp to 60°C: Many combi boilers are factory-set higher than they need to be, to a high 75°C or 80°C, which stops the boiler from running efficiently.
• Turn off pre-heat facility: Some combi boilers keep an amount of water heated up when it is not in use. Turning this off can save money and your water will still stay consistently hot when it is needed.
• Readjust thermostatic radiator valves (TRVs) outside the living room to 1.5 degrees cooler than before: The valves on the side of your radiator can reduce energy bills by allowing you to control the temperature of each room individually. Making a slight 1.5°C change outside the living room by changing the radiator setting from 5 to 3 will save money, while ensuring that the most well-used room stays at the same temperature.
• Reduce thermostat temperature to 19°C: A home heating thermostat measures the air temperature and automatically turns a boiler or heating system on and off to keep a home at a steady, comfortable level. Turning this down slightly to 19°C (from 20°C) can help save money.
• Close curtains at night: Around a third of Brits don’t close all the curtains in their home at night, despite this helping save energy. The curtains act as a barrier, preventing heat from escaping through the window and keeping the home warmer for longer.
• Shorter heating season (Oct - March): With 2027 predicted to be one of the hottest years on record, turning the heating off before April, when the weather is milder, can help make further savings.

Katy King, director of Nesta’s sustainable future mission said: “Living costs across the UK are increasing year-on-year and energy bills have reached a three-year record high. It’s no secret that many people will find their energy bills difficult to afford this winter - households will likely be feeling the strain.

“But our research highlights that there is a quick and easy adjustment that many people can do at home to save £57. And if they want to save more, they can head to our website and follow our guidance on five more free, money-saving household measures to more than triple their savings to £220.”

Since its inception in 2022, the Money Saving Boiler Challenge has helped 3.1 million households save almost £300 million . If a further 1 million households join the challenge and reduce their boiler flow temperature, this could increase the saving on bills by £57 million. If all six adjustments are made by those 1 million households, this could save £220 million in household energy costs across the UK by April.

Rebecca Dibb-Simkin, Chief Customer Officer at Octopus Energy, said: “When bills are biting, every penny counts. We need to get homes off expensive, unpredictable gas and onto cheaper electric heating - but in the meantime, there are simple ways to make the heating you’ve got work harder for your money. Just five minutes tweaking your boiler settings could save you £57 a year. That’s five minutes well spent - and money better off in your pocket.”

Linsey McGarrigle, Chief Operating Officer at British Gas said: “We're pleased to be working with Nesta on the Money Saving Boiler Challenge and helping more households understand the simple actions they can take to reduce their energy costs. Helping customers keep their homes warm and their bills as affordable as possible is important to us, and small changes, such as reducing a combi boiler's flow temperature, can make a real difference without affecting comfort.

“Every winter, our engineers visit millions of homes across the UK, giving us an opportunity to share practical energy-saving advice directly with customers, alongside support to help them get the most from their heating systems and use energy more efficiently.”

Jo Alsop, Co-founder of The Heating Hub/Warmer Academy said: "The cost of living crisis hasn’t gone away and energy bills remain a real pressure for households. But there are still simple, practical things people can do to save money without sacrificing comfort. Lowering the flow temperature on a suitable boiler is one of them. We’re really pleased to support Nesta in bringing this important message back to households, helping more people cut their bills and stay warm.”

Toby Allen, Director of Business Development at EDF said: “With EDF’s price cap predictor suggesting energy bills could rise above £2,000 in the first half of next year, many households will understandably be concerned about the pressure this could put on their finances. That’s why there’s never been a better time to look at simple ways to reduce energy use and save money this winter. We’re proud to support Nesta’s Money Saving Boiler Challenge, which offers practical, low-effort tips that can help households cut their bills while staying warm and comfortable at home.”

The campaign is supported by official partners Which?, British Gas, NRLA, Octopus, Heating Hub, Energy UK, OVO and EDF.

Ends

For more information on the analysis or to speak to one of the experts involved, please contact Bryony Ravate, Campaign Officer on [email protected] Spokespeople are available for broadcast interviews.

Notes to editors

1. A summary of the evidence used in the campaign is available on Nesta’s website.
2. In June - July 2026, Nesta reanalysed figures from the Salford Energy House experiment in 2022 in line with current gas prices and average gas use across the UK. The Salford Energy House evidence suggests that homes that currently have their boiler flow temperatures set to 75°C could reduce gas consumption for space heating by 10% by setting their flow temperature to 60°C, or by 14% by turning down to 55°C. Assuming that homes use approximately 75% of their gas on space heating, this means that these reductions in gas demand would result in overall gas consumption savings of around 7%(for those turning down to 60°C) or around 10% (for those turning down to 55°C). Based on the 7% saving on total gas use from reducing flow temperatures from 75°C to 60°C (reported above), we estimate that an average household with an annual gas consumption of 9,876 kWh would save 720 kWh of gas per year. At a price of 7.97p per kWh of gas (the September–December 2026 price cap unit rate for gas), this equates to £57 per year. However, this estimate includes the expectation that reduced flow temperature will also lead to longer heating up times. How much longer depends on the radiator sizes and other characteristics of the house and heating system.
3. Nesta estimates that a combination of six free energy saving measures could cut a total of £220 million from home energy bills if 1 million people took part. The six free measures are: reducing flow temperature to 60°C for combination boilers, turning off pre-heat facilities on combination boilers, readjusting existing TRVs outside the living room to 1.5°C cooler than before, reducing thermostat temperature from 20 to 19°C, closing curtains at night, take part in a shorter heating season (October to end of March).

About Nesta

Nesta is a research and innovation foundation that designs, tests and scales solutions for the biggest challenges of our time.

Driven by a vision to improve the lives of millions of people, our focus up to 2030 is on three missions: breaking the link between family background and life chances, halving obesity and cutting household carbon emissions.

We work with partners to develop high-potential solutions and test them as they evolve, drawing on expertise in qualitative and quantitative research, data science, behavioural science and design.

Once confident in the effectiveness of a solution, we take it to scale. We create national policy proposals, develop consumer-facing products and services, build and spin out commercial ventures and harness the power of the arts.

We work with two specialised units: BIT applies a deep understanding of human behaviour to help clients achieve their goals. Challenge Works designs and runs challenge prizes to spark innovation in science, technology and society. Find out more at nesta.org.uk