Window Grants UK 2026 Government Help Walkthrough
If your home has draughty single-glazed windows, you may wonder whether the UK government offers financial help to replace them. Rising energy bills make efficient glazing a priority for many households. The answer is yes, but the support is tightly targeted.
Window grants are available in 2026 through the Energy Company Obligation (ECO4) scheme, but only for low-income households and only after loft and cavity-wall insulation is already in place. The typical grant value per window is £300 to £500, leaving the householder to pay little or nothing (GOV.UK, 2026).
The Energy Company Obligation (ECO4) is the main source of free window grants in 2026
ECO4 is a government scheme that obligates large energy suppliers such as British Gas, E.ON, and Octopus Energy to fund energy-efficiency improvements for low-income and vulnerable households. Replacement double or triple glazing is eligible only as a “secondary measure” once loft and cavity-wall insulation are in place (GOV.UK, 2026).
The grant covers the full or partial cost of replacement windows, not repairs. The exact amount depends on the property’s energy assessment and the supplier’s funding pot. Eligibility is tied to receiving certain means-tested benefits or meeting local-authority flexibility criteria (Ofgem ECO4 Delivery Guidance, 2026).
What a new window saves per year and how long the payback takes
A typical A-rated double-glazed window saves around £100 to £135 per year in heating costs compared with a single-glazed window, according to Energy Saving Trust figures (Energy Saving Trust, 2026). For a typical three-bedroom semi-detached house with ten windows, total annual saving is roughly £1,000 to £1,350 if all single-glazed units are replaced.
Payback period for a fully self-funded installation (no grant) is typically 15 to 20 years. With an ECO4 grant covering most of the cost, payback drops to under five years (Energy Saving Trust, 2026).
Quick numbers cost, saving, and grant value for a typical home
| Item | Value | Source |
|---|---|---|
| Average cost per new double-glazed window (supply + install) | £400–£600 per window | Energy Saving Trust, 2026 |
| Typical grant value per window under ECO4 | £300–£500 | Ofgem, 2026 |
| Annual energy saving per window (single to A-rated double) | £100–£135 | Energy Saving Trust, 2026 |
| Annual energy saving per window (old double to new A-rated) | £30–£50 | Energy Saving Trust, 2026 |
| Typical number of windows in a 3-bed semi | 10 | ONS housing stock data |
Who is eligible for a window grant in 2026
Primary eligibility is receipt of one of the qualifying means-tested benefits: Pension Credit, Universal Credit (with low earnings), Income Support, Income-based Jobseeker’s Allowance, Income-related Employment and Support Allowance, Housing Benefit, Working Tax Credit, or Child Tax Credit (Ofgem ECO4 Ordering Guidance, 2026).
Local Authority Flexible Eligibility (LA Flex) expands access to households not on benefits but with low income and high fuel costs. Each council sets its own criteria (GOV.UK, 2026). The property must have an Energy Performance Certificate (EPC) rating of D, E, F, or G. Windows are only funded after insulation measures are addressed (DESNZ ECO4 scheme rules, 2026).
Check if your EPC rating qualifies for ECO4 funding
The grant process step by step from application to installation
Step 1: Check eligibility via an online eligibility checker or contact an MCS-certified installer who works with ECO4 funding. Step 2: An assessor visits the property to confirm loft and cavity-wall insulation status and to conduct an energy audit. Step 3: The installer submits a funding application to the obligated energy supplier. Approval takes 2 to 4 weeks. Step 4: Installation is carried out by an MCS-certified and TrustMark-registered firm. The householder pays only the co-payment (if any) after the grant is applied. Step 5: Post-installation inspection by the supplier or scheme administrator verifies work meets standards (Ofgem ECO4 Delivery Guidance, 2026).
How to verify an installer is properly certified for grant-funded work
All installers must hold MCS (Microgeneration Certification Scheme) certification for windows. This is a non-negotiable requirement for ECO4 funding (MCS website, 2026). The installer should also be registered with TrustMark, the government-endorsed quality scheme that provides consumer protection and dispute resolution (TrustMark, 2026).
Do not pay a large upfront deposit. Legitimate grant-funded work typically requires only a small co-payment (if any) after the grant is approved (Citizens Advice, 2026).
How to spot an ECO4 grant scam
The direct answer window grants are available in 2026, but only for low-income households and only after insulation is done
Yes, window grants exist in 2026 through the ECO4 scheme. They are not available to all homeowners, only to those on qualifying benefits or meeting LA Flex criteria. The grant covers replacement windows (not repairs or secondary glazing) and is a secondary measure, meaning the home must already have adequate loft and cavity-wall insulation. Typical grant value per window is £300 to £500, leaving the householder to pay a small co-payment or nothing at all (Ofgem, 2026).
What happens after the grant – maintenance, warranty, and resale value
New windows covered by ECO4 come with a minimum 10-year insurance-backed guarantee from the installer (TrustMark, 2026). Maintaining the warranty requires annual cleaning of frames and drainage channels and prompt repair of any seal failures.
Replacing single glazing with double glazing can increase a property’s EPC rating by 5 to 10 points, which can raise resale value by roughly 1 to 2% according to Nationwide and EST research (Energy Saving Trust, 2026).
Does new glazing add value when selling your home?
Frequently Asked Questions
Yes, through the ECO4 scheme, but only for low-income households and after loft and cavity-wall insulation is done, per GOV.UK (2026).
The typical grant is £300 to £500 per window, depending on the property's energy assessment and the supplier's funding pot, according to Ofgem ECO4 guidance (2026).
You qualify if you receive means-tested benefits or meet local-authority flexibility criteria. Check with your energy supplier or local council, per GOV.UK (2026).
Yes, ECO4 requires loft and cavity-wall insulation to be installed first, as window replacement is a secondary measure, per Ofgem ECO4 Delivery Guidance (2026).
An A-rated double-glazed window saves around £100 to £135 per year versus single glazing, according to the Energy Saving Trust (2026).
Yes, if you are a low-income tenant on qualifying benefits, but the landlord's permission is needed. Contact your energy supplier, per GOV.UK (2026).
