Spain's municipalities now have a powerful weapon against empty homes: an IBI surcharge of up to 150%. The measure, embedded in the Housing Law, targets owners with four or more residential properties left vacant for over two years without justified cause.

The Big Picture

The surcharge comes at a time when Spain's housing market is under severe strain. Rental prices remain elevated in major cities, short-term tourist lets are proliferating, and families struggle to find affordable homes. The policy aims to unlock thousands of long-term vacant units and increase supply.

Under the law, a dwelling is considered permanently vacant if it has been continuously empty for more than two years without a justified reason. However, the surcharge is not automatic: each municipality must define its own fiscal ordinance, procedures, and evidence requirements. The measure specifically targets large holders—those with four or more residential properties—not owners of a second home used occasionally.

“"The maximum surcharge can reach 150% of the IBI tax bill, but exemptions exist for temporary relocations, renovations, legal disputes, and second homes within legal limits."”

By the Numbers

• Base surcharge: Municipalities can levy an additional 50% on the net IBI tax for vacant homes.
• Duration penalty: The surcharge rises to 100% if the property has been empty for more than three years.
• Multiple-property penalty: An extra 50 percentage points can be added if the owner has two or more vacant properties in the same municipality.
• Maximum total: In the most severe cases, the combined surcharge can reach 150% of the original IBI bill.

Why It Matters

This marks a significant shift in Spanish municipal tax policy. Previously, holding vacant properties carried no additional cost, encouraging owners to wait for capital appreciation. The IBI surcharge introduces a holding cost that can make it unprofitable to keep units empty.

The biggest losers are large portfolio owners, especially those with four or more units in a single municipality. For them, a 150% surcharge could mean thousands of euros in extra annual taxes. Small landlords with one or two properties are unaffected.

The policy's success hinges on municipal implementation. Cities like Barcelona and Madrid have already signaled interest in applying the surcharge. However, the law leaves room for interpretation, and some owners may challenge the surcharge in court.

What This Means For You

For real estate investors: If you own four or more residential units in one municipality, audit your portfolio now. Properties vacant over two years could trigger a surcharge of up to 150%. Consider renting them out or selling before the tax hits.

For second-home owners: You're largely safe. The surcharge targets permanently vacant homes, not occasional-use second residences. As long as your property is used within legal limits, you won't face the penalty.

For renters and homebuyers: This policy could increase rental supply over the next few years, potentially moderating price growth. But the effect will depend on how aggressively municipalities enforce the surcharge and how owners respond.

1. 1Review the number of properties you own in each municipality.
2. 2Identify units vacant for more than two years without valid justification.
3. 3Explore options: traditional rental, regulated short-term rental, or sale.

What To Watch Next

The coming months will determine how municipalities incorporate these surcharges into their 2027 fiscal ordinances. High-tourism cities like Barcelona, Madrid, Valencia, and Málaga are likely to move first.

Legal challenges are almost certain. Large holders may argue the surcharge is confiscatory, potentially taking the case to Spain's Constitutional Court. The outcome could set a precedent for similar measures across Europe.

The Bottom Line

The empty home IBI surcharge is a powerful but limited tool. Its impact will depend on political will and owner adaptation. If enforced rigorously, it could unlock thousands of homes and ease rental pressure. If it remains a paper tiger, it will be another patch on a structural problem. 2026 marks the beginning of a new fiscal era for Spanish housing.

Additional Context: Implications for the Rental Market

The implementation of this surcharge not only affects owners but also has deep implications for the rental market. In cities like Barcelona, where the vacancy rate is estimated at around 5% of the housing stock, mobilizing these units could increase rental supply by 10-15%, according to estimates from real estate consultancy CBRE. However, there is a risk that some owners may choose to sell rather than rent, which could increase sales supply but not necessarily ease rental pressures. Moreover, additional costs could be passed on to tenants if owners decide to rent at higher prices to compensate for the tax. This effect is particularly relevant in high-demand areas like Madrid, where rental prices have risen 12% year-on-year in 2026.

Near-Term Catalysts

In the coming months, several municipalities are expected to approve their fiscal ordinances for 2027, with the IBI surcharge as a central element. Barcelona has already announced it will apply the maximum 150% surcharge starting January 2027, while Madrid is evaluating a 100% surcharge for homes empty over three years. Valencia and Málaga are also studying similar measures. Additionally, the central government may publish a regulation clarifying application criteria, which would accelerate municipal adoption. On the other hand, large holders such as socimis and investment funds are lobbying for exemptions for properties under renovation or with inheritance issues.

Investor Perspective: Mitigation Strategies

For investors with portfolios of four or more properties in one municipality, the most immediate strategy is to audit the occupancy status of each property. Those vacant for more than two years should be prioritized for rental or sale. One option is to sign long-term rental contracts (minimum 5 years) to avoid being considered permanently vacant. Another alternative is to allocate units to regulated tourist rentals, although this requires licenses and may be subject to municipal restrictions. In extreme cases, selling non-strategic properties may be the most efficient option to avoid the surcharge. Investors should calculate the annual cost of the surcharge (up to 150% of IBI) and compare it with the potential rental yield to decide the best course of action.

Fiscal and Legal Implications

The IBI surcharge is applied to the net tax bill, which for a typical home in Madrid can range from €500 to €1,500 per year. A 150% surcharge would add between €750 and €2,250 extra, a significant cost for low-yield properties. Legally, owners can appeal the surcharge if they prove the property is not permanently vacant (e.g., with temporary rental contracts or renovation certificates). However, the burden of proof lies with the owner, which can be complex. The Constitutional Court may rule on the constitutionality of the surcharge if an appeal is filed, but this could take years. In the meantime, municipalities have free rein to apply the measure.

International Comparison

Spain is not the only country taxing empty homes. France applies a tax of 12.5% to 60% of the cadastral value for vacant homes in high-demand areas, while the UK allows municipalities to double the council tax for unoccupied properties. In Canada, Vancouver imposes a tax of 1% to 3% of property value for empty homes. Spain's measure is more aggressive in percentage terms but only affects large holders, making it less universal. International experience suggests such taxes can reduce vacant homes by 10-20% in the first few years, but may also lead to increased sales and reduced investment in new developments.