What is the Solidarity Tax of Great Fortunes?
The Solidarity Tax on Large Fortunes is a tax that has existed in Spain since January 1, 2023, after the publication in the BOE of the Law 38/2022, of December 27. Its origin is in the proposal of Unidas Podemos and, as we have indicated, it was initially designed to last two years.
The ISGF is collected by the State and no Autonomous Community can establish bonuses or reductions, nor can it pocket the amount collected.
The initial objective of this tax is increased collection and harmonization of regional regulations. It is a direct, personal and complementary tax to the Wealth Tax (IP).
To fully understand the current situation, which we will talk about in the next section, it is important to keep in mind that the tax rate is calculated taking into account what has been paid in the IP, so that, in general, the new tax fundamentally affects taxpayers from the Autonomous Communities that do not have the subsidized IP.
What does the solidarity tax tax?
The Solidarity Tax on Large Fortunes taxes the net assets of natural persons that exceed the 3,000,000 euros (without prejudice to the exempt minimum of 700,000 euros, applicable to both residents and non-residents since the 2023 modifications).
ISGF tax types:
| Net worth | Applicable type |
| Between 3 and 5,347,998.03 euros | 1,7% |
| Between 5,347,998.04 and 10,695,996.06 euros | 2,1% |
| More than 10,695,996.06 euros | 3,5% |
What is the current situation of the Great Fortunes Solidarity Tax?
In the beginning, the purpose of the Ministry of Finance with the creation of the ISGF was to compensate for the lack of collection in the territories where the IP was subsidized. Thus, the richest taxpayers who managed to escape the IP due to their tax residence, with the arrival of the new tax, had to pay an amount of a similar structure to the Treasury, instead of to their community. On the other hand, those who did pay it—because their autonomy did not apply discounts—could deduct 100% of the fee on the new one.
The autonomous reaction
What has been the consequence? The Autonomous Communities that previously subsidized the IP have stopped doing so so that the money from large fortunes stays in autonomous territory instead of passing into the hands of the State.
Madrid is a clear example: in 2023 it was the largest taxpayer of state tax with 555 million euros. Now, the reactivation of the IP has redirected that income to the regional administration. Other communities like Andalusia, Galicia, Cantabria, Balearic Islands, Murcia and Extremadura They also followed the path of the Government of Isabel Díaz Ayuso.
As a result, ISGF collection has fallen drastically: from 619 million euros in 2023 to only 38 million in 2024, according to data from the Tax Agency.
New 2026: Elimination of tax discrimination against non-residents
One of the most important developments of 2026 is the resolution of the Central Economic-Administrative Court (TEAC) of December 18, 2025, which eliminates tax discrimination that existed for foreign citizens in the Solidarity Tax of Great Fortunes.
The "tax shield" now available for non-residents
The TEAC has established that non-residents can apply the 60% limit (known as "fiscal shield") that protects taxpayers so that the joint payment of Personal Income Tax, Wealth Tax and ISGF does not absorb more than 60% of their Personal Income Tax tax base.
Previously, the Tax Agency prevented foreign citizens from applying this reduction, claiming that it could not verify their income tax returns because they lived in another country. However, the Supreme Court established in rulings in October and November 2025 that this restriction was discriminatory and violated the EU principle of free movement of capital.
Possibility of claiming returns
This resolution opens the door for foreign citizens to claim a refund of what was overpaid in the Great Fortunes tax since its entry into force in 2023. Non-residents must provide the necessary documentation (a declaration similar to the Personal Income Tax in their country) so that the Tax Agency can calculate the new fee by applying the tax shield.
Other changes to the Solidarity Tax of Great Fortunes
Royal Decree-Law 8/2023, of December 27, was published in the BOE of December 28, 2023, which established three fundamental changes:
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Indefinite validity
The Solidarity Tax of the Great Fortunes now has indefinite validity from 2024. It is no longer a temporary tax, until the taxation of assets is reviewed within the framework of the reform of the regional financing system.
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Exempt minimum for non-residents
The exempt minimum of 700,000 euros is extended to non-residents (obliged by real taxation), and this modification is retroactive from the creation of the ISGF. This allows non-residents who paid the tax in 2022 to request a refund.
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Mandatory electronic presentation
It establishes the obligation to present ISGF declarations electronically. The submission period is from July 1 to July 31 of each year (with a deadline of July 26 if the result is to be deposited and the payment is direct debited).
Who must pay the Great Fortunes Solidarity Tax?
The ISGF will continue to be maintained even though its collection is residual after the latest changes. The Government has made this decision to ensure that all autonomous communities tax wealth homogeneously within their territories, thus promoting greater tax equity at the national level.
Taxable persons of the ISGF:
The taxpayers of this tax are: natural persons residing in Spain with a net worth greater than 3,000,000 euros. Specifically, the Solidarity Tax directly affects the Autonomous Communities that have a 100% discount on the IP or because they have lower rates than the corresponding Solidarity Tax.
Situation by Autonomous Communities
Several autonomous communities have modified their IP regulations with effect from 2023 so that the planned ISGF collection remains in their respective territories:
- Madrid and Andalusia: ISGF taxpayers cannot apply the general 100% bonus to the IP, but rather a variable bonus that is calculated by the difference between the full IP quota and the full ISGF quota.
- Balearic Islands: The exempt minimum is raised from 700,000 euros to 3,000,000 euros.
- Cantabria: A 100% bonus is established that will not apply when the net assets, discounting the exempt minimum, exceed 3,000,000 euros.
- Galicia: The 50% bonus is reduced by the amount payable to the ISGF. In addition, the marginal tax rate of the last tranche of the IP has been increased to make it coincide with that of the ISGF.
- La Rioja: With effect from 2025, a variable bonus is introduced in the IP that must be reduced by the full ISGF quota.
- Catalonia: The 2022-2023 IP rate is extended, which includes a last tranche for liquidated bases greater than 20 million euros.
In short, the measures adopted in these Autonomous Communities aim to ensure that the hypothetical fee that would be payable in the ISGF is entered into the corresponding autonomous community, within the scope of the IP.
Comparison: how Great Fortunes are taxed by Communities
| Autonomous Community | IP status | ISGF Impact | Collection |
| Madrid | Variable bonus from 2023 | Residual | Autonomous (IP) |
| Andalusia | Variable bonus from 2023 | Residual | Autonomous (IP) |
| Galicia | 50% reduced bonus | Shared (IP + ISGF) | Mixed |
| Catalonia | Extended rate with high section | There may be ISGF quota | Mixed |
| Cantabria | Variable bonus from 2024 | There may be ISGF quota | Mostly autonomous |
| Balearic Islands | Exempt minimum €3M from 2024 | Residual | Autonomous (IP) |
| Murcia | Exempt minimum €3M | Residual | Autonomous (IP) |
| Extremadura | 100% bonus from 2023 | Does not affect | Without property tax |
| Asturias | Maximum rate 3% | There may be ISGF quota | Mixed |
| Rest | No significant bonus | 100% ISGF deduction | Autonomous (IP) |
Frequently asked questions about the Solidarity Tax of Great Fortunes
From what assets should I pay the Solidarity Tax?
You must submit a declaration if your net worth exceeds 3,000,000 euros. However, an exempt minimum of 700,000 euros applies (for both residents and non-residents), so effective taxation begins from that threshold.
How is net worth calculated?
Net worth is calculated by adding the value of all your assets and rights (property, bank accounts, stocks, investment funds, etc.) and subtracting deductible debts. The first 300,000 euros of the value of the habitual residence are not included.
Can I deduct what I paid in the Wealth Tax?
Yes, from the ISGF fee you can deduct 100% of what was actually paid for the Wealth Tax in the same year. For this reason, in many Communities where the IP has been reactivated, the ISGF quota is zero or very reduced.
Do non-residents also have to pay the ISGF?
Yes, non-residents are taxed by real obligation on assets and rights located in Spain. From 2023 they can apply the exempt minimum of 700,000 euros and, from 2026, also the 60% tax shield following the TEAC resolutions.
When is the ISGF declaration submitted?
The declaration is submitted between July 1 and July 31 of the year following the fiscal year (if you domiciliate the payment, the deadline is July 26). The presentation must be made electronically using form 718.
Can I claim if I am a non-resident and I overpaid?
Yes, non-residents who paid taxes in 2023 and 2024 without being able to apply the tax shield can request rectification of their self-assessments and claim a refund of the overpaid, providing documentation of their personal income tax or equivalent in their country of residence.
What happens if my Autonomous Community has reduced the Wealth Tax?
If your Community has eliminated or reduced the IP bonus so that the collection remains in the autonomous territory (such as Madrid, Andalusia or Galicia), you probably do not have to pay the ISGF or it is residual, since you can deduct what was paid for the IP.
Is it true that the ISGF is no longer temporary?
Yes, although it was created as a temporary tax for 2022-2023, Royal Decree-Law 8/2023 made it permanent until property taxation is reviewed in the context of the reform of the regional financing system.
Conclusion: specialised advice for large assets
The taxation of large assets in Spain has become a complex scenario where the regional Wealth Tax and the state Solidarity Tax come together, with regulations that vary significantly depending on the Autonomous Community of residence.
The recent TEAC resolutions that eliminate tax discrimination against non-residents, added to the continuous regional regulatory changes, make it essential to have specialised tax advice for:
- Optimize the tax burden: Determine the most favorable Autonomous Community according to your financial situation
- Correctly apply deductions: Maximize IP deductions in the ISGF and the 60% tax shield
- Claim returns: Identify if you are entitled to refunds for improper payments, especially if you are a non-resident
- Plan your tax residence: Evaluate the fiscal impact of changing Autonomous Community
- Correctly value your assets: Apply specific valuation rules for each type of asset
In Strengthen We are specialists in taxation of large assets and we offer you:
- Custom analysis of your tax situation in the IP and ISGF
- Comparative simulations tax burden between Autonomous Communities
- Claims management for non-residents who overpaid
- Tax optimisation through asset structuring
- Regulatory compliance with presentation of model 718 and model 714 (IP)
- Track changes regulations that may affect your taxation
Do you have assets greater than 3 million euros? Are you a non-resident and think you overpaid in 2023 or 2024? Consult now with Afianza and our team of property tax experts will help you comply with your tax obligations in the most efficient way!
