The Dutch government’s ISDE subsidy (Investeringssubsidie Duurzame Energie en Energiebesparing) pays homeowners back for installing insulation, heat pumps, solar boilers, and heat network connections. The scheme has run since 2016 and is managed by RVO (Rijksdienst voor Ondernemend Nederland). It is not a loan or a tax deduction. RVO pays the subsidy directly to your bank account, typically within a few months of approval.
The budget is finite and does not roll over. That matters for timing, which we’ll get to.
What Qualifies in 2026
The ISDE covers four categories.
1. Insulation
Eligible measures include cavity wall insulation, interior and exterior wall insulation, roof insulation, floor insulation, and high-efficiency glazing (HR++ or triple).
One condition catches many applicants off guard: you must install at least two insulation measures to qualify on insulation alone. A single measure qualifies only when combined with a heat pump or solar boiler.
Each measure must also meet minimum thermal resistance (Rd) or U-values. Roof and floor insulation both require a minimum Rd of 3.5 m²K/W. RVO publishes the full table of requirements on their website.
2. Heat Pumps
Eligible types are air-to-water heat pumps, ground-source (geothermal) heat pumps, and hybrid heat pumps (heat pump plus condensing gas boiler). The model must appear on RVO’s approved product list. An unlisted model will be rejected regardless of its efficiency rating.
Hybrid heat pumps attract lower subsidies than full heat pumps, but are widely used in older Dutch homes where full electrification is not yet practical.
3. Solar Boilers
Solar water heating systems qualify if the model is on RVO’s approved list. They are less common than heat pumps but can be a good fit for homes with adequate roof exposure.
4. Connection to a Heat Network
If your municipality is building a district heating network, the cost of connecting your home qualifies for ISDE funding. This is increasingly relevant as more Dutch cities phase out natural gas.
Subsidy Amounts
Amounts vary by measure, home size, and installation specifics.
Insulation is subsidised per square metre, typically €5–€40/m², depending on type and Rd-value achieved. Cavity wall insulation sits at the lower end; exterior wall insulation with high Rd-values sits at the upper end.
Heat pumps receive lump-sum payments. A full air-to-water heat pump typically attracts €1,900–€4,500 or more, depending on capacity and efficiency class. Ground-source heat pumps attract higher amounts. Hybrid heat pumps are usually €1,000–€1,800.
Solar boilers attract €500–€1,500.
These amounts cover roughly 15–30% of total installation costs. For households below a certain income threshold, the subsidy can be up to 50% higher than standard rates.
The Application Process
Step 1: Plan your measures
Decide what you want to install and get quotes from certified installers. Check that every product is on RVO’s approved list before the installation date. If you are applying for insulation alone, confirm you have at least two qualifying measures.
Combining insulation with a heat pump is common and sensible: it maximises the subsidy and reduces the heating capacity the heat pump needs.
Step 2: Have the work done
The ISDE does not offer pre-approval. You invest, have the work completed, and then apply. This surprises many applicants. RVO subsidises completed installations, not plans.
Step 3: Gather your documentation
You will need:
- Invoices from your installer specifying what was installed, the product details, and the costs
- Proof of payment (bank statements)
- Product specifications confirming items meet required standards and appear on the approved list
- Your home’s address, ownership proof, and year of construction
The invoices must be detailed. “Insulation work – €5,000” is not sufficient. RVO requires the type of insulation, Rd-value, square metres installed, and specific product used. If your installer is not familiar with ISDE requirements, tell them before they issue the invoice.
Step 4: Apply via RVO
Submit your application through mijn.rvo.nl using your DigiD. The form asks for your details, the measures installed, and your uploaded documents.
Step 5: Assessment and payment
RVO targets an eight-week processing window, though it runs longer during busy periods. If your documentation is complete, the subsidy is paid to your bank account. Incomplete applications will trigger a request for clarification and add weeks to the timeline.
Common Reasons Applications Are Delayed or Rejected
Incomplete invoices. The most common problem. Missing Rd-values, product names, or square metres will trigger a clarification request.
Products not on the approved list. Verify every product before installation. Checking after the fact, once the application has been rejected, means the installation cannot be corrected retroactively.
Single insulation measure. The two-measure minimum is firm. A single insulated loft does not qualify unless combined with a heat pump or solar boiler.
Applying late. The ISDE runs on an annual budget. It has not run out mid-year in recent cycles, but it is not impossible. Do not leave a completed installation sitting for months before filing.
No DigiD. Setting one up takes time, especially if activation needs to happen by post. Sort it out before you start the process.
A Few Other Details
Stacking with other subsidies. Some municipal and provincial schemes can be combined with the ISDE; others cannot. Check with your local gemeente. The Warmtefonds (low-interest loans for sustainability measures) can typically be used alongside the ISDE.
Rental properties. The ISDE is for owner-occupiers. Landlords are subject to different rules. Tenants cannot claim it.
Energy labels. You do not need a specific energy label to apply. An assessment before and after installation can, however, be useful for documenting impact and may be relevant for other schemes or property value.
VvE (homeowners’ associations). Apartment building associations can submit collective ISDE applications for building-wide measures such as shared insulation or a communal heat pump.
Limitations Worth Knowing
The requirement to pay upfront before applying is a real barrier for households without available capital, even temporarily. The Warmtefonds and income-dependent top-ups address this partly, but not fully.
The Netherlands has around eight million homes, many of them old and poorly insulated. The ISDE is one part of a broader set of measures that includes the Nationaal Isolatieprogramma (targeting lower-income households) and local heat transition plans. The scale of what remains is large.
The Bottom Line
Check the RVO website for current approved product lists and subsidy amounts. Work with a certified installer who knows ISDE applications. Get the invoice details right before work is completed. Submit promptly after the work is done.
Disclaimer: This article is a general overview of the ISDE subsidy scheme and does not constitute financial or legal advice. The information reflects conditions as of May 2026. Subsidy requirements, eligible products, amounts, and budget availability change periodically. Verify current terms and requirements directly through the official RVO website (rvo.nl) or consult a qualified energy advisor before making investment decisions. We cannot be held responsible for any discrepancies or decisions made based solely on this article.
