“Bitcoin’s greatest triumph is forcing the Treasury to learn what a wallet is,” says de Fuenmayor.
According to the specialist, the “romantic fantasy” of absolute monetary anonymity “has disappeared.”
When does a digital asset like bitcoin (BTC) stop being an isolated—and sometimes ignored—economic fact and become something fully real in society? It’s not when Wall Street arrives, nor when it appears in exchange-traded funds (ETFs) or consulting reports. It happens when the tax authorities of the countries begin to pursue you persistently.
This is already happening in Spain, where the Tax Agency, which is the executing arm of the Ministry of Finance, has consolidated automated control through massive data crossing supported by artificial intelligence algorithms. This is a bureaucratic offensive against taxpayers that ratifies the State’s decision to prevent wealth from circulating freely, according to economist Carlos de Fuenmayor.
According to de Fuenmayor, the State – in this case the Spanish one – “may ignore a financial innovation for years, ridicule it, regulate it late or even demonize it from institutional forums, but it will never tolerate indefinitely the circulation of wealth without trying to place a box, an information model and, if necessary, a pedagogical sanction with an unequivocal purpose of collecting revenue.”
“The blockchain may be decentralized, but the Spanish Tax Agency remains stubbornly centralized and extraordinarily meticulous when it comes to following the money trail,” says de Fuenmayor.
The specialist explains that, due to this inspection pressure, “the romantic fantasy of absolute monetary anonymity has disappeared” from the environment of digital currencies, which, in essence, were born as a way to evade government controls on money.
De Fuenmayor is one of those who considers that the cryptocurrency fiscal ecosystem in Spain “is no longer an improvised jungle.” In his opinion, Spain has consolidated a highly specialized tax ecosystem around these assets, made up of tax specialists, lawyers, tax inspectors and experts who, according to him, have transformed what was previously a chaotic terrain into a structured and technical professional field.
This development marks the end of the improvised stage and puts an end to the idea of an opaque or invisible space for the Hacienda. And, indeed, cryptoassets have stopped being seen as a simple digital trend and have become fully active assets. integrated into the tax system of the Iberian country.
In fact, the proliferation of complex operations on platforms such as Binance, Kraken, MetaMask, Arbitrum, or DeFi protocols, has generated a demand for hybrid knowledge: professionals capable of navigating both the classic language of the Treasury, as well as the technical vocabulary of staking, bridges, liquidity pools, perpetuals, and on-chain movements.
In this context, the economist affirms that “Bitcoin’s greatest triumph is forcing the Treasury to learn what a wallet is.” According to the specialist, Cryptoassets have “definitely crossed a fiscal Rubicon.”
A “cast” of cryptocurrency tax professionals
Given this scenario, the specialist highlights that, in Spain, a veritable mass of professionals in cryptocurrency taxation has emerged, highlighting Sandra Adrián, founder of Modo Cripto; Jesús Lorente, partner of CL Cripto; José Antonio Bravo Mateu, from Fiscal Crypto; Sergi Andrés, from Abast Legal; José María Gentil Girón, Treasury inspector and author of the manual “Bitcoin and cryptoassets in personal income tax”; and Esteban Rivero, from Cero Uno.
De Fuenmayor describes this group as “a cast of brilliant, hyper-specialized professionals capable of moving simultaneously between the classic legal-tax language and the sometimes lysergic dialect” of the digital assets sector.
However, he warns about “upstarts” and “sticky advisors” that proliferate in the sector, remembering that, in Spain, Cryptocurrencies are taxed as property assets in the tax base of savings. Therefore, each sale or exchange generates a taxable event based on the difference between the acquisition and transmission value, with the possibility of offsetting losses with gains from the same year.
And although tools like CoinTracking help in the calculation, de Fuenmayor remembers that “automating is not the same as understanding,” since—he explains— human judgment is needed for complex operations.
In a recent context, on April 8, 2026, the Income 2026 campaign began with a massive crossing of data using artificial intelligence (AI). While on May 8, notifications from the Treasury were intensified requesting clarifications on operations for fiscal year 2025, as reported by CriptoNoticias. All this, under an environment of total fiscal control and surveillance.
In this scenario, de Fuenmayor asserts that the true maturity of the bitcoin and cryptocurrency ecosystem does not come from exchange-traded funds (ETFs) or Wall Street, but of this bureaucratic integration.
“The true sign of maturity of cryptoassets appears when an investor understands that a poorly documented DeFi operation can cost them more money in penalties than a bad investment in an altcoin,” he explained.
The evolution of fiscal control in Spain projects an even stricter supervisory panorama at a global level. Therefore, investors must assume that documentary transparency and proactive declaration will be essential requirements if they want to operate in the cryptocurrency market. Indeed, fiscal surveillance will be part of everyday life, although attacking financial privacy, also consolidating bitcoin—even more so—within the global financial architecture.