Aerothermal and Heat Pumps in 2026: How to Deduct Up to 40% of the Cost in Your IRPF

# Aerothermal and Heat Pumps in 2026: How to Deduct Up to 40% of the Cost in Your IRPF

Replacing individual boilers of fossil fuels (diesel, natural gas, coal) with clean climate systems is one of the priorities of the ecological transition in Spain. In 2026, the installation of aerothermal or high-efficiency heat pumps in the main residence opens the door to deducting 40% of the investment cost in the state portion of IRPF, with a maximum saving of up to 3,000 € per taxpayer.

Learn what technical characteristics the aerothermal machine must meet to be deductible, what documentation the Tax Agency requires, and how to optimally combine the Tax Office with state or regional subsidies.

What is aerothermal and why the Tax Office rewards its installation

Aerothermal or heat pump is a technology that extracts the thermal energy naturally contained in the outside air to generate heating, cooling, and Domestic Hot Water (DHW). Since it produces between 3 and 4 times more thermal energy than the electricity it consumes, the European directive classifies it as renewable energy.

To incentivize this voluntary technological change, the IRPF Law grants a tax deduction of 40% for works that allow reducing energy consumption of non-renewable primary energy by at least 30%, or improving the home's rating to reach class A or B in the energy efficiency label. Aerothermal meets this condition thoroughly.

Technical requirements that the aerothermal equipment must meet

The Tax Office does not accept any climatizer or domestic air conditioning unit as deductible aerothermal. The installed equipment must certify:

1. Seasonal performance (COP or SPF): The seasonal performance factor (Seasonal Performance Factor, SPF) of the heat pump must be above 2.5 to be considered renewable according to the IDAE standard and the Building Code Technical Regulation.
2. Residential location: The equipment must be installed in your main residence under property or long-term rental regime, or in a property-owned home that you have designated for permanent residential rental. Commercial premises, garages, and temporary recreational second homes are excluded.
3. Pre- and post-installation technical certification: Like in insulation reforms, it is mandatory to have an Energy Efficiency Certificate of the home drafted and registered before the start of the works (with an age of less than two years) and another after the boiler change (issued at most 12 months later).

Limits and amounts of the aerothermal deduction

The aerothermal deduction is calculated on the actual amounts paid during the fiscal year of the works (bank-processed invoices):

• Deduction percentage: 40% of the total investment.
• Annual deduction base maximum: 7,500 € per taxpayer.
• Maximum net deduction: 3,000 €.
• Multi-year extension: If the cost of aerothermal to heat an entire home exceeds 7,500 €, you can distribute the excess investment over subsequent years if it is a project of integral building rehabilitation of property owners (where the deduction rises to 60% with a maximum base of 15,000 €).

How to combine the IRPF deduction with regional subsidies

Many property owners request subsidies from the Next Generation plan to reduce the cost of the aerothermal equipment. It is vital to clearly understand the combined treatment of both incentives:

1. The subsidy will reduce the IRPF base: The tax deduction cannot overlap with money received from direct public funds.
2. Calculation formula:

$$\text{IRPF deduction base} = \text{Total installation investment} - \text{Granted subsidy}$$

1. Practical calculation example:

- Installed and legalized aerothermal budget: 10,000 €

- Regional Next Generation subsidy granted: 3,000 €

- Base for IRPF calculation: $10,000 € - 3,000 € = 7,000 €$

- Real deduction in your income (40% of 7,000 €): 2,800 €

- Net effective cost of your switch to aerothermal: $10,000 € - 3,000 € - 2,800 € =$ 4,200 € (¡You have obtained a 58% saving on the original investment!).

Documentation guide to justify your aerothermal to the Tax Office

When the AEAT performs a limited check of your 2026 IRPF, they will request you to provide:

• Previous and registered certificate before the start of the old boiler dismantling.
• Post-installation and registered certificate reflecting a 30% reduction in primary energy consumption.
• Copy of the Thermal Installation Certificate (RITE) issued by the qualified installer.
• Detailed invoice of the heat pump purchase and breaking down the labor cost.
• Bank transfer receipt to the climate system company.

How to declare the aerothermal deduction in the IRPF

The deduction applies in the income tax return for the year in which the installation is paid (invoice payment date, not installation date). If the invoice is paid in installments spanning two years, the base for each year is the amount effectively paid in that year.

The 40% deduction for reducing non-renewable primary energy consumption is reflected in the Annex A.3 of the model 100 (section on state deductions for home energy efficiency improvement works). The AEAT publishes the exact cell references each year in the practical income tax manual; consult the edition corresponding to the year you performed the work.

Remember that you will need the installer's NIF and the invoice amount to fill out the annex.

Consultation of the official regulation regarding thermal change

The percentages of base, limits, and validity of certificates for sustainable boilers and thermal equipment are governed by the national IRPF Law. You can check the current regulation:

→ Law 35/2006 of November 28 on the Personal Income Tax (BOE)

Frequently Asked Questions

Does aerothermal entitle you to a 40% or 60% deduction?

It depends on the scope of the work. For an installation in your main residence that reduces non-renewable primary energy consumption by at least 30%, the percentage is 40% (maximum base 7,500 €, maximum deduction 3,000 €). If the work is part of an integral energy rehabilitation of a property owners' building and the consumption reduction is at least 30% at the building level, the percentage increases to 60% (maximum base 15,000 €, maximum deduction 9,000 €).

Is the deduction compatible with the ICO loan or bank financing?

Yes. What matters is the amount effectively paid (the loan installment satisfied within the fiscal year), not the total cost of the work. Each year you can deduct 40% of the installments paid up to the maximum base of 7,500 €.

What happens if the subsidy is received the following year after installation?

The subsidy reduces the deduction base in the year it is received, not in the year of the work. If you pay the aerothermal in 2026 and receive the subsidy in 2027, in the 2026 income tax you can deduct the full cost. In 2027, when you receive the subsidy, you must regularize the over-deducted amount by returning the corresponding proportion.

Can I apply the deduction if I live in rent?

Yes, as long as you are the holder of a long-term rental contract and the installation is carried out in your main residence (not in a second home or commercial premises). The home does not need to be your property to apply the 40% deduction.

When does this deduction expire?

The deduction for energy efficiency improvement works was introduced by Law 10/2022 with validity until December 31, 2024, and later extended. Consult the current regulation of the fiscal year in which you perform the work, as the government may modify the deadlines.