Window Grants UK: What's Actually Available in 2026

Most people searching for a window grant don’t get one. That’s not pessimism, it’s how these schemes are built: nearly every route to free or subsidised windows in the UK requires you to already receive means-tested benefits or fall under a low household income threshold. If that’s not you, skip to the bottom section on what actually helps.

This article reflects scheme rules as they stood in September 2026. Funding schemes change eligibility, budgets and closing dates with little warning, so confirm current terms with the scheme provider before you plan around one.

Key points

• ECO4 targets benefit recipients and covers up to 100% of window replacement cost, but only single-to-double glazing upgrades, not swapping existing double glazing
• Warm Homes: Local Grant replaced most of ECO4’s role in England from April 2025, up to £15,000 for energy measures including windows
• Scotland’s main route is an interest-free loan, not a grant, capped around £8,000
• Wales and Northern Ireland run their own separate, smaller schemes
• If your income is above the thresholds, no scheme currently covers window replacement, full stop

Reading time: ~8 min

The grants that actually cover windows, at a glance

Note what’s missing from that list: the Great British Insulation Scheme. It gets mentioned constantly in window grant searches because the name sounds relevant. It isn’t. GBIS only ever covered cavity wall, loft and underfloor insulation, and it closed on 31 March 2026 regardless.

ECO4: still the biggest route, with a catch

ECO4 (Energy Company Obligation) is a levy on large energy suppliers, funnelled into free or subsidised home upgrades for households that qualify. For windows specifically:

• It funds replacing single glazing or failed old double glazing with modern double or triple glazing
• Funding can reach 100% of the job, calculated per property rather than a flat amount
• You apply through a participating energy supplier (British Gas, E.ON, EDF, OVO, Scottish Power, Utility Warehouse), not directly through government
• Standard eligibility runs through receiving Universal Credit, Housing Benefit, Pension Credit, Tax Credits or similar, plus an EPC rating of D or below
• ECO4 Flex widens that to households under roughly £31,000 income where someone’s health is affected by living in a cold home

Here’s the catch nobody puts in the headline: ECO4 was scheduled to close 31 March 2026. Some suppliers report a nine-month extension pushing that to 31 December 2026, but that’s not confirmed across the board as of this article’s publish date. If you’re relying on ECO4, ring a participating supplier this week rather than next month.

Warm Homes: Local Grant, the scheme that’s taken over

Launched April 2025 with £500 million behind it, the Warm Homes: Local Grant (WH:LG) is now England’s primary route for window funding outside ECO4. It runs through 270 local authorities and 73 regional projects until March 2028.

• Up to £15,000 for energy efficiency measures, including windows, plus a separate pot of up to £15,000 for low-carbon heating
• No household contribution required if you qualify
• Eligibility: household income £36,000 or below, or receipt of means-tested benefits, or living in an area flagged as deprived; EPC rating between D and G
• Applied for through your local council, not a national portal, so the actual process varies by area

Because it runs through local authorities, the practical experience differs sharply between a London borough with a dedicated retrofit team and a rural council handling it as one project among many. Ring your council’s housing or sustainability team directly rather than relying on a national webpage to tell you what’s live locally.

Scotland, Wales and Northern Ireland

Scotland doesn’t run a dedicated window grant. Home Energy Scotland offers an interest-free loan up to £8,000 (£9,500 in rural areas) for window upgrades, repayable rather than free, on top of separate grant funding for other measures. Warmer Homes Scotland exists too, but explicitly excludes new windows and double glazing, it’s insulation and heating only, plus secondary glazing in some cases.

Wales runs Nest, which covers windows for benefit recipients but tends to prioritise insulation and heating measures first, with windows funded where they’re the most cost-effective remaining upgrade. There’s no separate window-specific grant in Wales beyond what ECO4 and Nest already offer.

Northern Ireland’s Affordable Warmth Scheme covers up to £7,500 in energy measures including windows, for households with income under £23,000. Its status beyond March 2026 wasn’t confirmed at the time of writing, so treat it as provisional if you’re planning around it.

What you won’t find on most grant guides: the honest odds

Most articles on this topic list every scheme going and imply you’ll qualify for something. Realistically, if you’re a working household without a disability-related health condition and your income sits above roughly £30,000 to £36,000 depending on scheme and nation, none of the above applies to you. That’s most homeowners looking to replace tired double glazing that still technically works.

If that’s your situation, the honest move is to stop searching for a grant and start comparing installers properly instead. Three things move the needle more than chasing funding you won’t get:

1. 0% or low-interest finance offered directly by installers, which several run year-round regardless of government schemes
2. Timing the job for an installer’s quieter months (typically late autumn through midwinter), when some will shave a genuine discount off to keep crews busy
3. Getting three written, itemised quotes, since the spread between the cheapest and most expensive quote for an identical spec routinely runs into hundreds of pounds

At a glance

ECO4 and the Warm Homes: Local Grant cover most of what’s realistically available, and both are aimed squarely at low-income and benefit-receiving households. Scotland’s main option is a loan, not a grant. If none of the eligibility criteria fit your household, funding isn’t coming, put the energy into comparing quotes instead.

Comparing quotes without a grant

Our UK window and glazing installer directory lists FENSA and Certass registered companies by town and county, sourced from the Companies House register, so you can see who’s actually active in your area before you start ringing round. When you’re ready, our free quote request form sends your job to local registered installers with no obligation.

Worth reading alongside this: if energy efficiency is your main driver rather than cost, our guide to U-values and window energy ratings explains what actually determines how much heat your new windows will save you, grant or no grant.