What grants are available for new windows in Belgium?

The question of what grants are available for new windows is one that comes up regularly among homeowners planning renovation works in Belgium. New insulating windows are not only a smart investment in energy savings and comfort - they also qualify for regional renovation grants. These grants make the works more financially accessible, provided you meet the strict requirements around insulation values, ventilation and income category. This article gives you a clear overview of the grant amounts, the conditions and how to apply, so you can get started without any unwelcome surprises.

What renovation grants exist for new windows?

Belgian regions each run their own grant schemes for energy-efficient renovation works. In Flanders, the main scheme is the Mijn VerbouwPremie. These grants cover the installation of new exterior joinery with high-performance glazing, or simply the replacement of glass in existing frames. They target owner-occupiers and landlords, with amounts that vary significantly according to income category, the total invoice amount and whether the property meets the ventilation requirements.

The grant is calculated as a percentage of the investment costs (excl. VAT), with minimum and maximum amounts per category. For 2026, the rules that have been tightened since July 2025 apply, with stricter ventilation requirements and differentiated percentages by income. If you want to know exactly how much grant you can receive for new windows, you should first check your own situation using the official grant calculator for your region.

How much is the grant for new windows by income category?

Grant amounts depend on your income category (1 to 4, with 4 being the lowest incomes), the type of work and the invoice amount. The minimum invoice amount for the windows and doors category is 1,000 euros (excl. VAT), with a ceiling of between 10,500 and 11,000 euros depending on the period.

Base grant for new exterior joinery (windows + high-performance glazing)

• Income category 4 (lowest incomes): up to 35% of the investment (excl. VAT), with a maximum of 3,675 euros.​
• Income category 3 (lower-middle incomes): up to 25% of the investment, maximum around 2,750 euros.
• Highest income category (or investor): no percentage-based grant, but 16 euros per m² of newly installed high-performance glazing, capped at 40% of the invoice.

For an invoice of 8,000 euros (excl. VAT) in category 4: 35% = 2,800 euros in grants. In the highest category: 16 euros/m² of glazing, depending on the glazed surface area.

Grant for high-performance glazing replacement only (in existing frames)

If you are only replacing the glass - without new frames - a simplified grant of 16 euros per m² applies to all categories, with a maximum of 40% of the invoice. This is ideal for those looking to keep costs down without replacing the entire window unit.

Strict conditions: ventilation and insulation value

Not every new window will qualify. The grant for exterior joinery requires:

• Ventilation requirement: your home must comply with ventilation standards (system C or D) at the time of application. No compliant ventilation? Then only the glazing replacement grant remains available.
• Insulation value: a maximum Ug value of 1.0 W/m²K for the glazing.
• Age of the property: certain requirements relating to the year of construction or the energy performance certificate (EPC).​
• Contractor: works must be carried out by a registered contractor with a valid company registration number.​

For applications submitted from 1 July 2025 onwards, the ventilation requirement has been tightened for all categories. Check first whether your property qualifies, otherwise the grant will be limited to glazing replacement only.​

Application procedure, step by step

The procedure is fully digital via the online grant portal of your region:

1. Check in advance: use the official grant calculator to confirm your income category and the applicable conditions.
2. Have the works carried out: get the windows installed by a registered contractor (detailed invoice required).
3. Submit your application: within 2 years of the invoice date, with invoices, the energy performance certificate and proof of ventilation compliance.
4. Payment: within a few months after the file has been reviewed.​

You can combine the grant with other subsidies, such as the bonus tied to improving your property's energy label.​

Why new windows with a grant are a smart investment

On top of the grant, you save on energy bills: high-performance glazing reduces heat loss and heating costs by 10-20%. Your property value also increases, which is an advantage when selling. The grant shortens the payback period of the investment, which is typically 10-15 years.​

For homeowners, it is often worthwhile to bundle several works together - roof, walls, windows - to unlock higher grants. In 2024-2025, there was a spike in applications driven by the tightened requirements, so plan ahead.​

Municipal and additional grants

Beyond the regional grants, many local authorities offer additional subsidies for window replacement, often targeted at lower-income households or social housing tenants. Check with your local council, as these can add up to several hundred euros on top.

Practical tips to maximise your grant

• Choose certified glazing: make sure it meets Ug ≤ 1.0 W/m²K to qualify.​
• Upgrade your ventilation first: invest in a ventilation system if your home does not yet have one.​
• Optimise your invoice: bundle windows and doors within the maximum invoice ceiling.​
• Compare contractors: choose a registered contractor for a smooth application process.​

Anyone looking to replace their windows would do well to incorporate the grant into a broader renovation strategy. New windows not only improve comfort and value - they make your home more attractive to buyers in a market where energy efficiency is increasingly paramount.

Want to know how much your home could be worth with new windows? Request a free valuation. A local estate agent can assess the impact on market value and help you time your sale or renovation project.