Spain Solidaridad surcharge (ITSGF) — the €3m wealth tax

Spanish autonomous communities have the power to apply bonificaciones of up to 100% on Patrimonio. Madrid and Andalucía have used this for years to rebate Patrimonio to zero — making them attractive for HNW residency relative to Cataluña or Valencia. Politically this was contentious: critics argued the regional bonificaciones undermined the wealth-tax base nationally.

The national government introduced ITSGF (Solidaridad) in Real Decreto-ley 18/2022 to apply a national-level surcharge on net wealth above €3m, with no regional bonificación available. Crucially, the surcharge allows residents to deduct Patrimonio paid — so the effect is to ensure that everyone above €3m pays at least the surcharge rate, even if their region rebates Patrimonio to zero.

Originally framed as a two-year temporary measure (covering 2022 and 2023 wealth positions), Solidaridad has been extended through subsequent legislation and is in force for 2026. Its long-term political future is uncertain but the current position is: it's the de facto floor on Spanish HNW wealth tax above €3m.

Solidaridad applies a three-bracket structure above the €700,000 personal allowance:

• €700,000 – €3,000,000: 0% (this band is the Patrimonio territory, no Solidaridad)
• €3,000,000 – €5,347,998: 1.7%
• €5,347,998 – €10,695,996: 2.1%
• Above €10,695,996: 3.5%

The €700,000 personal allowance is the same as the Patrimonio default. The primary-residence allowance of €300,000 also applies. So the effective starting point for any Solidaridad bill is €3,000,000 of net wealth (or €3,300,000 if you hold a primary residence valued at €300k+ to deduct).

Where it bites: a Madrid resident with €5m net wealth pays €0 Patrimonio (regional 100% rebate), but pays Solidaridad on €5m minus €700k minus €300k = €4m above the allowances → bracket 1 covers €2.35m at 1.7% = €39,950, and bracket 2 covers the remaining €1.65m at 2.1% = €34,650 → total Solidaridad ~€74,600/year.

Solidaridad allows you to deduct the Patrimonio you've actually paid in the same year from the Solidaridad bill. This is the mechanism that equalises the regional differences at the HNW level.

Worked example with €5m net wealth, comparing two regions:

• Madrid resident: €0 Patrimonio (100% regional rebate) → Solidaridad bill ~€74,600 → no Patrimonio to credit → pays €74,600 total
• Cataluña resident: Patrimonio ~€60,000-€70,000 depending on exact composition → Solidaridad gross bill ~€74,600 → Patrimonio credit ~€65,000 → net Solidaridad ~€9,600 → total ~€69,600-€80,000

The net wealth-tax burden at €5m is broadly similar across Madrid and Cataluña post-Solidaridad. Below €3m, Cataluña still costs more (no Solidaridad applies); above €10m, the regional differences become small in relative terms.

Where Madrid/Andalucía still win post-Solidaridad: the filing simplicity (zero-Patrimonio return is shorter and lower-audit-risk) and the bracket positioning at the €3m-€5m band, where Cataluña residents pay Patrimonio but get only partial Solidaridad credit because the Patrimonio brackets at this wealth band are slightly different from Solidaridad brackets.

• Below €3m net wealth: Solidaridad doesn't apply. The regional choice (Madrid vs Andalucía vs Cataluña vs Valencia) drives your wealth tax bill — Madrid and Andalucía win cleanly.
• €3m–€10m net wealth: Solidaridad equalises most of the regional gap. Madrid/Andalucía still have edge through filing simplicity and bracket positioning, but the absolute saving versus Cataluña is small. Regional choice driven more by other factors (climate, lifestyle, schools).
• Above €10m net wealth: Both Patrimonio and Solidaridad apply at the upper bracket of 3.5%. Madrid/Andalucía still produce slightly cleaner outcomes but you're paying material wealth tax everywhere. Consider whether Spain is the right destination at all — Portugal (no wealth tax), Gibraltar (Cat 2 capped at £42,380), or Italy's flat-tax regime become more competitive at this level.
• Asset structuring: Solidaridad applies the same exemptions as Patrimonio — qualifying business assets, certain pension schemes, etc. Pre- move restructuring of UK assets into Solidaridad/Patrimonio-friendlier wrappers is a real planning area for HNW movers.
• Non-resident position: Solidaridad applies to non-residents on Spanish-situs assets too, with similar regional-rule election available from 2024 onwards. Non-residents with €3m+ of Spanish-situs assets (e.g. Marbella property HNW buyers) need to factor this in.

• Assuming Madrid = zero wealth tax above €3m. True for Patrimonio (100% regional rebate); not true for Solidaridad (full national rate applies). Madrid HNW still pays significant Solidaridad.
• Forgetting Solidaridad is creditable against Patrimonio paid. Some calculators / older guides treat them as additive — they're not in Cataluña/Valencia where Patrimonio is paid.
• Filing Solidaridad late. Same deadline as Patrimonio (typically end of June, year following). Late filing penalties are similar to IRPF — 5%-150% depending on delay and intent.
• Treating Solidaridad as “temporary” for planning purposes. It was originally framed as 2022-2023 only; it's been extended each year since. Plan as if it's permanent.
• Underestimating valuation aggressiveness. Hacienda has been more aggressive on valuations under Solidaridad than under Patrimonio historically. Get UK assets professionally valued at 31 December each year if there's any prospect of being above €3m.