Your US LLC and Spain: the tax trap the setup was sold to avoid.

The US LLC is one of the most common structures foreign founders bring to Spain, and one of the most misunderstood once they arrive. The problem is not that a US LLC is illegitimate. It is that the two tax systems classify the same entity in opposite ways — and that mismatch, combined with where the business is actually run, produces outcomes that the "form an LLC and pay no tax" pitch never mentions.

Spanish corporate tax residence does not turn on where a company was incorporated. Under Spain's Corporate Income Tax Law, an entity is a Spanish tax resident — and taxed on its worldwide income — if it meets any of three tests. A US LLC fails the first two, but the third is where founders walk in without noticing.

Even where the LLC is not deemed Spanish-resident, the hybrid classification creates friction. The US treats the LLC as fiscally transparent — income flows to the member. Spain, through its tax authority's rulings, has generally treated a US LLC with legal personality and limited liability as an opaque entity, comparable to a Spanish company, rather than as transparent. Two systems, two characterisations of one entity. The practical effects:

• Timing mismatch — the US taxes the member on profits as they accrue; Spain may tax the resident member only on distributions, treated as dividends. The years do not line up, which complicates foreign tax credit relief.
• Treaty friction — treaty benefits require income to be "derived by a resident." A disregarded single-member LLC can struggle to claim treaty relief in its own name, and hybrid-entity provisions have to be worked through carefully.
• Double taxation risk — where the two systems tax different persons at different times on the same income, relief is not automatic and depends on getting the characterisation and the credits right.

Suppose the LLC is genuinely managed from the US and is not Spanish-resident. It can still be taxed in Spain if it has a permanent establishment (establecimiento permanente) there — a fixed place of business, or a dependent agent habitually concluding contracts on its behalf. A founder living in Spain and doing the substantive work of the business is exactly the fact pattern that raises a PE question. Where a PE exists, its profits are taxed in Spain under non-resident income tax, broadly at the corporate rate.

Separate from how the LLC is taxed, the Spanish-resident individual behind it has their own obligations.

• Distributions as dividends — if Spain treats the LLC as opaque, money taken out is generally taxed in the member's hands as dividend income, on the IRPF savings scale (rates rising into the high twenties per cent for larger amounts).
• Transparencia fiscal internacional (CFC) — where the LLC earns mainly passive income and is lightly taxed, Spain's controlled-foreign-company rules can attribute that income to the resident owner as it arises, whether or not it is distributed.
• Foreign asset reporting — a Spanish tax resident holding an interest in a foreign entity above the reporting thresholds must declare it on the informative return for assets held abroad. This is an information obligation with its own penalty regime, independent of the tax due.

None of this makes a US LLC wrong. It makes it situational. The deciding factor is where the business is really run and who the customers are.

A US LLC can still make sense for genuinely US-centred activity — US customers, US operations, US management — held by a founder whose Spanish position is properly planned around it. What rarely works is the influencer template: incorporate in Delaware, move to Spain, run everything from a laptop in Valencia, and expect the LLC to be invisible to the Spanish tax authorities. It is not invisible, and the cost of discovering that after the fact is far higher than the cost of structuring it correctly first.