How-To · Updated April 2026

How to Apply for an ECO4 Grant for Insulation in 2026

ECO4 is the UK's largest home-insulation grant — and most eligible households still haven't claimed it. If you qualify, it can cover 100% of the cost of loft, cavity or internal-wall insulation (typically £2,500–£14,000). This 2026 step-by-step guide walks through the full eligibility matrix, the 4-step application process, how to avoid cold-call scams, and what to do if your installer tells you you're "not eligible" when you actually are.

Valid until March 2027 100% funded if eligible No cold-callers needed
Check Eligibility → How to Apply
PAS 2035 Certified Installers
Ofgem-Regulated Scheme
100% Funded (If Eligible)
Open Until March 2027
Avoid Cold-Callers
Quick Answer

How do I apply for ECO4?

Go direct to an Ofgem-listed ECO4 installer — don't wait for cold-callers. The four steps are:

  1. Check eligibility (income-based benefit OR local LA Flex referral)
  2. Find an Ofgem-registered ECO4 installer (we list how below)
  3. Book a free PAS 2035 Retrofit Assessment — the installer does this at no cost
  4. Receive your Medium Term Improvement Plan, then installation

Timeline: 4–12 weeks from first call to completed install. Your out-of-pocket cost: zero if fully eligible.

Who Qualifies

ECO4 Eligibility in 2026: Two Routes In

There are two routes to ECO4 funding — most homeowners only know about the first, and miss out on the second entirely.

Route 1

Qualifying Benefits (automatic)

If you or anyone in your household receives one of these benefits, you qualify automatically:

  • Universal Credit
  • Income-based Jobseeker's Allowance (JSA)
  • Income-related Employment and Support Allowance (ESA)
  • Income Support
  • Pension Guarantee Credit
  • Working Tax Credit / Child Tax Credit
  • Housing Benefit
  • Child Benefit (income thresholds apply)
Route 2 (most missed)

LA Flex Referral (local authority)

If you don't claim any benefits but your home has EPC rating D, E, F or G, your local council may still refer you under "LA Flex" rules. Common qualifying criteria:

  • Household income below £31,000/year (threshold varies by council)
  • A resident with a long-term health condition affected by cold
  • Over-65 household
  • Rural property with high heating costs

How to apply: search "[your council] LA Flex ECO4" — most have a one-page form online.

What's Funded

What ECO4 Pays For in 2026

ECO4 covers insulation and heating measures that improve a home's EPC rating by at least one band. Exact coverage depends on your property type, fuel source and current EPC — but here's the typical 2026 picture:

Measure Typical Cost (private) ECO4 Coverage Your Contribution
Loft insulation (top-up) £450–£900 100% £0
Cavity wall insulation £1,200–£2,500 100% £0
Internal wall insulation £8,000–£14,000 Full OR partial £0 to £2,000
External wall insulation £9,000–£16,000 Full OR partial £0 to £3,000
Room-in-roof insulation £1,800–£3,500 100% £0
Underfloor insulation £1,200–£3,200 100% £0
Boiler replacement (broken) £2,200–£3,800 Full OR partial £0 to £1,500
First-time central heating £4,000–£7,500 100% £0

Wall insulation grants are means-tested on EPC uplift delivered. If one measure alone won't move you from (say) EPC E to D, the installer will propose a "whole-house plan" combining several measures to hit the target.

Step-by-Step

The 4-Step ECO4 Application Process

Step 1

Confirm your eligibility route

Either check which qualifying benefits are in your household, or look up your council's LA Flex criteria online. Save any award letters and benefit statements as proof — you'll need them at the retrofit assessment.

Step 2

Find an Ofgem-registered installer

Search Ofgem's ECO4 installer directory (free to use) or search TrustMark's database for PAS 2035-accredited retrofit installers in your postcode. Get 2–3 quotes — yes, even though it's "free," installers compete on what they'll include.

Step 3

Book the PAS 2035 retrofit assessment

The installer sends a Retrofit Assessor (free to you). They survey the whole home, check for damp / ventilation issues, and produce a Medium Term Improvement Plan. This is the legal document that unlocks ECO4 funding.

Step 4

Approve the plan and install

Review what's proposed (sign nothing before you understand the plan), sign the ECO4 declaration, and the installer will schedule the work. Most installs complete within 2–6 weeks of plan approval; the installer handles all Ofgem paperwork.

£14k
Max ECO4 grant per home
£700
Avg annual bill saving
8 wks
Typical application-to-install
Mar 2027
ECO4 scheme end date
Watch Out

ECO4 Scam Warnings — 5 Red Flags

ECO4 is a legitimate government-backed scheme, but the cold-call industry around it is rife with scams. These are the five red flags to walk away from immediately:

  1. Cold calls or unsolicited doorstep visits. Legitimate ECO4 installers rarely cold-call. Ofgem explicitly warns against this route.
  2. Asking for money upfront. ECO4 is funded by energy suppliers — you should never pay anything before an installation. Any "assessment fee" is a scam.
  3. Pressure to sign on the day. PAS 2035 gives you a 14-day cooling-off period. Legitimate installers welcome you taking time to compare.
  4. "Free solar panels with your insulation". ECO4 does NOT fund solar panels. If offered, the firm is almost certainly bundling a paid product.
  5. No TrustMark or Ofgem registration. Every ECO4 installer must be listed in Ofgem's ECO4 installer directory AND TrustMark-registered. Verify both before agreeing to anything.
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FAQs

ECO4 Grant Questions (UK 2026)

No — this is the biggest misconception about ECO4. If you're not on a qualifying benefit, you can still qualify under the "LA Flex" route via your local council. Most councils allow households earning under £31,000/year, or with vulnerable residents, or with poorly-rated EPC (D or below), to be referred. Contact your local council's energy team directly; search "[council name] LA Flex ECO4".
Typical end-to-end timelines in 2026 are 4–12 weeks. The first call to your installer takes minutes; the PAS 2035 retrofit assessment is usually booked within 1–3 weeks of initial contact; the Medium Term Improvement Plan is produced within 2 weeks of the survey; and the installation itself is scheduled 2–6 weeks later depending on the installer's pipeline. Loft and cavity work is much faster than wall insulation (which involves scaffolding and drying times).
For loft, cavity, room-in-roof and underfloor insulation, ECO4 is genuinely 100% funded — no hidden costs. For the more expensive measures (internal or external wall insulation), ECO4 may cover the full cost OR require a partial contribution of £1,000–£3,000 depending on your property and eligibility strength. The retrofit assessment is always free to you. Any installer asking for an upfront fee is running a scam.
Yes, but only with your landlord's written consent. Private tenants can access ECO4 if they meet the qualifying criteria, but the landlord must agree to the work and sign the installer's paperwork. Social housing tenants have a separate Social Housing Decarbonisation Fund route — ask your housing provider. Houses in Multiple Occupation (HMOs) have more restrictive rules; check with your council's environmental health team.
The £700 figure is the UK average annual saving for a household upgrading from EPC E to EPC C — typical for a solid-walled pre-1945 home getting full insulation. Smaller upgrades (e.g. loft-top-up only) save £100–£250 a year; the biggest savings come from internal/external wall insulation combined with heating upgrades, which can save £1,100+ a year on 1930s semis on gas. Your installer's Medium Term Improvement Plan includes a specific estimated saving for your property.
Always get a second opinion. Some installers only focus on the most profitable measures and will turn away applicants whose homes don't suit their commercial model. If you've been told "you don't qualify," try two more Ofgem-listed installers AND approach your local council's LA Flex team directly. Many households turned away by one installer are happily funded by another. If you're turned away by multiple installers, Citizens Advice has a free ECO grant advice line that can check your case.

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