With the arrival of 2026, Homeowners in Spain have extra room to save on their income tax return. If they take advantage of the deductions linked to energy efficiency improvements. The Government has decided to extend a package of tax incentives that allows for a significant reduction in income tax for those who undertake renovations that reduce energy consumption in their homes.
This extension, approved at the end of the year and already published in the Official State Gazette (BOE), opens the door to a package of tax incentivesThe measure is part of the strategy of modernization of the residential park and a boost to sustainability, while offering a respite to many family budgets considering home renovations.
Legal framework and deadlines for applying the deduction
The regulatory framework for these tax benefits is set out in the Real Decreto-ley 16/2025, which establishes the extension of deductions for energy efficiency improvement works in the Personal Income Tax. The text clarifies that the validity of these tax benefits, which initially ended on December 31, 2025, It extends until the end of 2026 for individual homes and until 2027 for entire residential buildings..
In practice, this means that Amounts paid for works carried out on homes up to December 31, 2026 will be eligible for deduction. (usual or intended for rental) provided that the conditions set out in the Personal Income Tax Law are met. In the case of actions on entire residential buildings, the deadline is extended by one more year, until December 31, 2027.
There is one particularly important date: The final energy efficiency certificate, in the case of individual works in homes, must be issued before 1 January 2027For residential building renovations, the post-work certificate must be issued before January 1, 2028. If this deadline is missed, the right to apply the deduction is lost.
These dates mark the tax calendar for many taxpayers who, if they want to benefit from the deduction, They will need to organize the works and the processing of the energy certificates with some leeway. It's not enough to simply carry out the reform: all the documentation must be correctly issued and within the deadline.
What is considered an energy rehabilitation project?
Not just any action will do for the reform to have an effect on personal income tax. The regulations define energy efficiency improvement works as those that achieve at least a 30% reduction in the building's non-renewable primary energy consumption or that allow one to achieve a energy rating "A" or "B" on the official scale. At the most basic deduction levels, work that reduces heating and cooling demand by 7% is also considered.
In practice, This type of action includes renovations such as replacing windows with models that have better insulation, improving the thermal envelope, and replacing equipment with more efficient ones. or interventions on the facade and roofprovided that the result translates into the required improvement in energy indicators. Actions on installations that use fossil fuels, such as new gas or oil boilers, are expressly excluded.
To demonstrate that the work meets the conditions, The owner must have two energy efficiency certificates for the property: one issued before the start of the work (valid if it has been issued no more than two years prior to the start of the work) and another later, once the renovation is finished, signed by a competent technician.
These two certificates allow for a comparison of the property's energy performance before and after the renovation and serve as a basis for proving to the Tax Agency that The required reduction in consumption or improvement in rating has been achievedWithout that documentary proof, the deduction cannot be applied, even if considerable investments have been made.
Who can benefit: housing types and taxpayers
The deductions are primarily intended for Individuals who pay income tax and who own their main residence or homes intended for rentThe regulations also cover the case of properties that are not yet rented, but are "awaiting" rental, provided that they are finally put on the market within the specified deadlines.
In the case of communities, the incentive is aimed at owners' or owners of multi-unit buildings undertaking comprehensive energy rehabilitation projects. Each owner, based on their share of ownership in the community, may apply their proportional share of the investment as the basis for the deduction in their income tax return.
This approach allows both those who renovate a home individually and those who participate in a community outlay They can access deductions that can reach up to 3.000 euros per year. For many older buildings, especially in urban areas with a high concentration of high-rise housing, energy-efficient renovations can represent a significant overall economic benefit.
It is also worth remembering that State deductions can coexist with direct public aid from rehabilitation programsHowever, any subsidies received must be deducted from the tax base for personal income tax purposes. In other words, the Tax Agency does not allow deductions for expenses that have already been fully or partially covered with public funds.
How much money can be deducted: the three levels of aid
The scheme approved by the Government does not establish a single deduction, but a stepped system depending on the energy impact of the work and the type of building. The figure of 3.000 euros appears as an annual limit both at the intermediate level for homes and at the upper level for buildings, although the way to arrive at that amount is different in each case.
First of all, there is the basic level, which allows deductions of up to 1.000 eurosThis applies when minor home improvements reduce heating and cooling demand by at least 7%. In this category, taxpayers can deduct 20% of the amounts paid from their income tax return, up to a maximum annual deduction of €5.000. The practical result is a maximum deduction of €1.000 on the tax return.
The second step is the most significant in terms of direct impact, as it is the one that intermediate levelThis intermediate level is reserved for larger projects that achieve at least a 30% reduction in non-renewable primary energy consumption or that improve the building's energy rating to an "A" or "B". In this case, the deduction increases to 40% of the amount paid, with a maximum annual base of €7.500; hence the €3.000 savings limit.
Finally, there is the upper section, aimed at energy rehabilitation works in entire residential buildingsIn this case, when the improvements to the property achieve a 30% reduction in non-renewable primary energy consumption or reach an energy rating of "A" or "B", each owner can deduct 60% of their investment, calculated according to their share in the community. The maximum annual deduction is €5.000 per taxpayer, so the maximum annual deduction is again €3.000.
The unique feature of this last level is that There is the possibility of carrying over the excess non-deductible base for four additional tax yearsIf a homeowner's investment exceeds the annual threshold of €5.000, they can continue to apply the remaining amount in their income tax returns in subsequent years, up to a maximum accumulated threshold of €15.000. In numerical terms, this allows for a total deduction of up to €9.000 (60% of €15.000) spread over several years.
Practical example of a €3.000 deduction in Income Tax
To understand the true scope of these figures, the case of a homeowner who participate in an energy rehabilitation of your building during 2026Let's assume that the community undertakes a facade renovation and insulation improvement at a cost that, for this particular neighbor, translates into a special assessment of 5.000 euros, according to their share.
If the works achieve the required energy improvement (reduction of non-renewable primary energy consumption by at least 30% or a jump to an "A" or "B" rating), and that improvement is certified by the corresponding certificates, The owner can claim a 60% deduction on their tax return on those 5.000 euros. The result is a direct discount of 3.000 euros on your full tax liability, provided you have sufficient tax liability to absorb the deduction.
If the same taxpayer had to assume a larger expense, for example of 12.000 euros, in the first year they could only apply the 5.000 euros per year limit as the basis for the deduction. The remaining 7.000 euros would be pending application in the following four fiscal years....until reaching the maximum accumulated base of €15.000. In this way, deductions would be made successively until a total savings of €9.000 is achieved over several years.
For improvements to individual homes, the system works similarly but with different percentages and maximum thresholds. A homeowner who invests €7.500 in improvements that significantly enhance their home's energy efficiency and reach the intermediate level will qualify. you will be able to deduct 40% of that amount, which translates into those 3.000 euros of deduction that mark the top of the bracket.
Payment terms and eligibility for aid
One of the issues that generates the most confusion is the method of payment. The fine print of the Official State Gazette (BOE) is clear: Amounts paid in cash do not give rise to a deductionIn order for the work to be considered for income tax purposes, all payments to renovation companies, installers, and technicians who issue certificates must be made through [the relevant tax authority/bank/etc.]. credit or debit card, bank transfer, nominative check or deposit into an account at credit institutions.
Furthermore, when calculating the basis for the deduction, Any public subsidies received by the taxpayer for those same works must be deducted.For example, if you receive direct aid from a regional or national rehabilitation program, that amount is deducted from the investment for income tax purposes. The tax authorities thus aim to prevent the same expenditure from receiving two full public benefits.
It is also key to keep in mind that The different energy efficiency deductions are incompatible with each other with respect to the same projectIn other words, the basic and intermediate levels cannot be applied simultaneously to the same transaction. The taxpayer must classify the modification within the corresponding bracket and apply only the deduction associated with that level.
In addition to all this, there is the prohibition of Include as a deductible expense the cost of installing boilers or equipment that run on fossil fuelssuch as gas or diesel. The incentive's philosophy is to reward investments that truly reduce environmental impact and energy consumption, hence the strict regulations regarding this type of equipment.
Formal requirements and documentation to be kept
Beyond the type of work or the amounts, the application of the deduction It depends largely on the taxpayer scrupulously complying with the formal requirements.The Tax Agency may at any time require supporting documentation that proves both the reality of the investment and the energy improvement achieved.
Among the documents that should be kept are: The complete invoices from renovation companies, installers and technicians, the bank payment receipts and the energy efficiency certificates before and after the work. The general recommendation is to keep this documentation for at least four years from the end of the voluntary filing period for the declaration, a period in which the Tax Agency can begin audits.
In the event of an inspection, the Tax Administration will verify that The work complies with the established technical conditions, the payments have been made by the accepted means, and the dates of certificates and invoices match the legal deadlines.Any discrepancy may result in the loss of the deduction and the obligation to return the amounts unduly applied, with the corresponding surcharges and interest.
For this reason, many tax advisors recommend that, before starting renovations of a certain amount, the owner Consult a professional or review the regulations in detail. to be clear about which actions entitle you to a deduction, which bracket they fall into, and how they should be properly documented.
All these measures make energy efficiency deductions a relevant tool for those thinking about renovating their home or building: if used properly, they allow you to reduce your income tax bill by up to 3.000 euros per year and, in some cases, accumulate up to 9.000 euros in tax savings over several years, while improving home comfort. the property increases in value y energy consumption is reduced in a context of high energy prices.
