Tax Investigations and Enquiries
Expert defence and strategic guidance for businesses and HNWI facing AEAT scrutiny
Tax investigations and enquiries in Spain can be stressful, time-consuming, and financially risky — especially when the process involves complex cross-border issues, corporate structures, or high-value assets. Whether triggered by a routine review (comprobación limitada) or a full inspection (inspección tributaria), the consequences can include substantial tax liabilities, interest, and penalties.
With GCO as your representative, you’ll have a clear strategy from day one, protecting your financial position, minimising disruption to your operations, and ensuring full compliance with Spanish tax law.
- Reduce exposure to penalties and surcharges through strategic negotiation
- Ensure compliance with all information requests and legal deadlines
- Protect your rights during AEAT interviews, information gathering, and on-site inspections
- Gain peace of mind with an expert team managing the process from start to finish
The Risks of Handling an AEAT Investigation Alone
Navigating the Spanish tax system without specialist advice can cost far more in the long run
- Have you received a notification from the Agencia Tributaria (AEAT)?
- Unsure why your tax return was selected for review?
- Concerned about the implications of providing incomplete or incorrect information?
Attempting to manage a Spanish tax investigation without expert representation can lead to:
- Disclosure of unnecessary information that widens the scope of the investigation.
- Missed opportunities to reduce penalties through proactive measures.
- Re-opening of previous tax years for further assessment.
At GCO, we have decades of experience defending clients in Spanish tax investigations and enquiries— from straightforward compliance checks to highly complex investigations involving multiple jurisdictions.
Tax Investigations and Enquiries Support
Pre-investigation risk review
We conduct a thorough, proactive review of your tax position to detect and resolve potential issues before they attract the attention of the Agencia Tributaria. This includes:
- Analysing previous tax returns and corporate filings for inconsistencies.
- Assessing the tax implications of high-value transactions, restructurings, and asset sales.
- Reviewing cross-border arrangements, foreign asset reporting (Modelo 720), and transfer pricing compliance.
This service is particularly valuable for multinational groups, high-net-worth individuals, and companies undergoing significant changes, as it allows us to implement corrective measures that reduce the likelihood of a formal investigation.
Tax Investigations and Enquiries Support
AEAT representation
Once appointed as your authorised representative (representante voluntario), we manage every interaction with the Agencia Tributaria, ensuring your legal rights are fully protected. Our representation includes:
- Drafting and submitting all written responses and documentation.
- Attending all in-person and virtual meetings on your behalf.
- Ensuring compliance with statutory deadlines to avoid surcharges.
- Controlling the scope of the investigation so it remains focused and contained.
Our objective is to relieve you of the stress and administrative burden, while ensuring the case is resolved efficiently and on the most favourable terms possible.
Tax Investigations and Enquiries Support
Voluntary disclosures and regularisation
If past irregularities exist — whether intentional or due to error — acting before AEAT initiates a formal investigation can significantly reduce your exposure. We:
- Evaluate your position and quantify the potential liabilities.
- Select the most appropriate disclosure route, including regularización voluntaria, before the tax authority contacts you.
- Prepare and file all amended returns, calculations, and supporting documentation.
- Negotiate to secure the highest possible reduction in penalties (up to 50% in certain cases under Spanish law).
By taking control of the narrative early, we help clients close past issues quietly, without unnecessary reputational or financial damage.
Tax Investigations and Enquiries Support
Why Choose GCO?
Seamless communication for nationa & international clients. Our bilingual tax lawyers and economists work fluently in Spanish and English, removing the risk of misunderstandings with both clients and the authorities. This is especially critical when explaining complex positions or negotiating settlements.
From prevention to litigation — under one roof. We offer a complete service lifecycle: risk reviews, AEAT representation, voluntary disclosures, dispute resolution, and court appeals. This means you won’t need to manage multiple advisers or repeat the same explanations to different firms.
Negotiation skills. We know the procedures, the language, and the leverage points that can reduce penalties, limit the investigation’s scope, and shorten its duration.
Absolute discretion. Investigations can create uncertainty among stakeholders. We manage your case with the highest level of confidentiality to protect your reputation, investor confidence, and ongoing operations.
Tax Investigations and Enquiries Support
“Will hiring specialists make the tax authorities suspicious?”
It’s a common concern — but in practice, the opposite is true.
The Agencia Tributaria often views professional representation as a sign that the process will be handled efficiently, accurately, and within the law.
When clients try to handle an enquiry themselves, small errors, delays, or incomplete responses can unintentionally raise more questions and prolong the investigation.
By contrast, having GCO manage the process:
- Shows you take the matter seriously and are committed to full compliance.
- Ensures clear, precise communication that addresses AEAT’s requests without oversharing or creating new lines of enquiry.
- Speeds up resolution, as we know exactly what information is relevant and how to present it.
- Protects your position by preventing procedural missteps that could harm your case.
Process and Methodology
A Clear Path to Excellence for your Company
Our customer-centric process is tailored to your specific needs. From initial analysis to strategy implementation, we are with you every step of the way.
- Initial Situation Analysis
- Development of Customized Strategies
- Solutions Implementation
- Continuous Monitoring and Adjustment
Preguntas frecuentes
Answering your doubts about tax investigations and enquiries
What triggers a Spanish tax investigation?
An AEAT enquiry may start for various reasons: random selection, discrepancies between your declared figures and third-party data, transactions that the tax authority considers high-risk (such as large capital gains, restructurings or cross-border transfers), or intelligence shared under international tax information exchange agreements.
In many high-value cases, the trigger is not a single error but a combination of factors that raises the risk profile.
How long does an AEAT investigation take?
The duration depends on the scope and complexity of the case. A limited review (comprobación limitada) might conclude within three to six months, while a full inspection (inspección tributaria) can last up to 18 months — and in complex cases involving multiple jurisdictions, this period can be extended to 27 months under Spanish law. Early, proactive management can often shorten the process.
Do I have to attend meetings in person?
In most cases, no. As your authorised representative, GCO can handle all correspondence, documentation and meetings directly with AEAT. Your attendance is only required if the tax authorities specifically request your personal testimony — and if that happens, we prepare you thoroughly so you know exactly what to expect.
What happens if irregularities are found during a tax inspection?
If AEAT identifies errors or omissions, they will typically issue a proposed adjustment (propuesta de liquidación provisional) detailing the additional tax, interest, and any penalties due. You have the right to respond, present evidence, and challenge their conclusions before a final assessment is issued.
In serious cases, AEAT may open additional years for review or refer the matter for potential criminal proceedings.
Having GCO involved from the outset helps control the narrative, limit the scope of adjustments, and negotiate reductions in penalties.
How often are tax inspections conducted?
There’s no fixed schedule — inspections are risk-driven rather than purely random.
High-value transactions, international operations, or activity in sectors considered high-risk by AEAT are more likely to trigger an inspection.
Some companies may go years without a review, while others may face checks more frequently due to their profile.
A proactive compliance strategy, backed by periodic internal reviews, is the best way to reduce the likelihood of repeated investigations.
Beyond the Investigation
Ongoing tax advisory services
A successful outcome in a tax enquiry is only part of the story. The next step is to strengthen your compliance, optimise your tax position, and prevent future disputes.
International taxation. For clients with cross-border operations, assets or investments, we design tax-efficient structures, apply double tax treaties, and coordinate compliance in multiple jurisdictions. This ensures you remain compliant globally while minimising your overall tax burden.
Inheritance and succession planning. Protect and transfer your wealth or family business without unnecessary tax exposure or legal conflict. Our specialists in inheritance and succession planning manage the fiscal, legal, and strategic aspects to ensure a smooth transition across generations.
Ongoing tax advisory & compliance. We provide continuous support for corporate and personal tax obligations — from optimising annual returns to advising on the tax implications of major transactions — so you stay ahead of potential risks and changes in Spanish tax law.
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Conoce a Nuestros Expertos en Fiscalidad
Experiencia y conocimiento a tu servicio para una gestión fiscal óptima.
Managing Partner
Tax Department Senior Manager
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