Spain ↔ Italy
The oldest corridor in terms of bilateral treaty (DTT since 1977, with a recent amending protocol). Intense movement of professionals and executives between Madrid-Barcelona-Milan-Rome. Critical point: the interaction between the Spanish Beckham Law and the Italian Régime degli impatriati. Specific treaty clauses limit the application of the DTT to those who opt into these regimes.
Spain ↔ Mexico
More than 8 billion euros in annual trade and more than 6,500 Spanish companies operating in Mexico. DTT in force since 1994 with a 2015 amending protocol. Reduced withholding rates on dividends (0%-10%), interest (4.9%-10%) and royalties (10%). Modernised anti-abuse clauses.
Italy ↔ Mexico
The least visible corridor but with growing activity, especially in Italian manufacturing that produces in Mexico for re-export to the US. Italy-Mexico DTT in force since 1991 with an amending protocol. Typical sectors: fashion, automotive, food, specialised machinery.
Triangulations
The true value of a firm specialised in the three countries lies in triangular operations: a Spanish parent with an Italian subsidiary operating in Mexico, a Mexican holding with an investment in an Italian company with a Spanish commercial presence, an Italian family office with tax beneficiaries in Spain and assets in Mexico. These structures require the simultaneous coordination of three tax regimes, not just sequential application.