Klimabonus 2026 in Luxembourg: amounts, conditions and MyGuichet.lu application

Klimabonus bundles the Luxembourg state's subsidies for residential energy renovation and renewables. It is run by the Ministry of the Environment, with Klima-Agence handling technical advice. In 2026 it covers eight work families: building envelope (roof, façade, floor, windows), mechanical ventilation, photovoltaics, storage batteries, heat pumps (air-water, ground-water, air-air), biomass heating, solar thermal domestic hot water, and EV charging stations.

On a well-combined full renovation, a single household frequently accumulates more than €40,000 in subsidies. The rule of thumb: the more structural the intervention, the higher the subsidy, and the bonus for the energy class reached can increase the renovation aid by 20 to 50 %.

The table below shows the most-requested caps for a single-family house. Actual amounts depend on installed capacity, treated area and achieved performance. For the official detail always check the solar subsidies page and the relevant Klimabonus factsheet on MyGuichet.lu.

The increased amounts apply to requests for an agreement in principle submitted between 1 January 2026 and 30 June 2027. Amounts checked on 27 September 2026. The applicable amount is always the one in force on the date a complete application is filed.

Five cross-cutting conditions apply regardless of the technology:

• The dwelling must be located in Luxembourg and used as the main residence.
• The applicant must be owner, co-owner or tenant with the owner's written consent.
• Works must be carried out by a company holding a Luxembourg business licence and registered with the Chambre des Métiers. DIY installations are not funded.
• The complete file must be submitted within 4 years from 31 December of the invoice year (charging station: within the following year). For energy renovation, an agreement in principle is mandatory before works start.
• Installed equipment must meet the regulation's performance thresholds (minimum SCOP for heat pumps, efficiency for biomass, U-value for windows).

Since 2024, co-ownerships have a specific regime allowing each co-owner to claim their share of the subsidy.

Photovoltaic: nominal capacity ≥ 2 kWp, run for self-consumption (the applicant waives payment for exported electricity), IEC-certified modules, certified inverter.

Battery: usable capacity ≥ 2 kWh, manufacturer warranty of at least 10 years or 6,000 cycles, thermal runaway protection. Must be coupled to a PV system in the same building.

Heat pump: SCOP ≥ 3.8 (air-water) or ≥ 4.3 (ground-water) per EN 14825, low-GWP refrigerant. The old fossil boiler must be removed and hauled off to qualify for the higher replacement amount.

Insulation: capped U-values (0.15 W/m²K roof, 0.20 façade, 0.90 windows). The installer's conformity certificate must state material thickness and thermal conductivity λ.

EV charger: smart OCPP-compatible charging point with sub-metering, installed by a licensed electrician.

Since 2023 the Klimabonus application is filed exclusively online via MyGuichet.lu. Procedure:

• Log in on www.guichet.lu with a LuxTrust product (Token, Smartcard, Signing Stick) or a Luxembourg eID. A private space must be created beforehand.
• Open the procedures catalogue, search for "Klimabonus" and select the factsheet matching your technology (e.g. "Aid for photovoltaic installation").
• Click "New application". MyGuichet.lu generates a pre-filled form.
• Fill in the technical details: capacity or area, brand, model, serial numbers, commissioning date.
• Attach the required documents: paid itemised final invoice, installer's conformity certificate, plan/schematic, company's business licence, bank details, plus Klima-Agence advisory report if you claim the increased bonus.
• Sign the application electronically with LuxTrust and submit. Acknowledgement of receipt within 24 h.
• Track the file in the "My procedures" tab. Average 2025 processing time: 4 to 6 months from complete submission to payment.

Tip: prepare one PDF per document (under 10 MB, A4). 70 % of rejected files are rejected for an unreadable page, a missing stamp or an invoice that does not itemise the equipment.

Klimabonus can be combined with several other instruments:

• Super-reduced 3 % VAT on works in a dwelling at least 10 years old used as the main residence, tax benefit capped at €50,000 per dwelling, not automatic.
• Klimaprêt: 1.5 % interest subsidy on a climate loan, taken into account up to €100,000.
• Social top-up: 10 % to 100 % of the Klimabonus amount on top for households below certain income ceilings.
• Municipal subsidies: many municipalities add a local premium (typically 10,25 % of the state aid) for PV, heat pumps or insulation.
• Class bonus: with energy advice, the renovation aid is increased by 20 %, 30 % or 50 % if the home gains at least 2 classes and reaches class C, B or A/A+.
• Heat pump: higher amount when it replaces fossil or direct electric heating, and +€2,000 for an order placed between 1 January 2026 and 30 June 2027.

On a typical 1980s house (façade + roof + air-water heat pump + 8 kWp PV + battery), 45 to 60 % of the total cost can be covered by public aid.

• Invoicing before the company was licensed: any invoice dated before the installer's Luxembourg licence disqualifies the file.
• Missing the deadline: 4 years from 31 December of the invoice year (charging station: 1 year).
• Using a non-Luxembourg company: no local business licence disqualifies the entire invoice.
• No proof of removal of the old boiler: the higher replacement amount will not be granted.
• Underrated equipment: entry-level PV modules or heat pumps often fall short of Klimabonus performance thresholds. Ask your installer for a written statement of conformity with the current Klimabonus regulation.

Klimabonus is especially profitable on solar installations, which combine a direct grant, 3 % VAT, self-consumption or feed-in revenue, and measurable property value uplift. To go deeper:

• The Luxembourg solar portal provides the profitability calculator, an explanation of self-consumption and typical cases by roof size.
• The full guide to solar subsidies covers feed-in tariffs, Creos connection, coupling with a storage battery and the documents to prepare.

On broader projects, the most profitable order is almost always: first the envelope (insulation, ventilation), then the generator (heat pump), then PV and optionally the battery. This sequence correctly sizes the heat pump and PV and puts the class bonus within reach.