AEAT Tax Inspection Defence: From First Notice to Full Resolution

An AEAT tax inspection (actuaciones inspectoras) is the most comprehensive — and most consequential — tax audit procedure under Spanish law. Governed by Arts. 141–159 of Law 58/2003 (LGT), the inspection covers all taxes, all periods within the statute of limitations, and all accounting records and documents. Art. 150 LGT establishes a general maximum duration of 18 months from the initiation notice (27 months for complex cases involving large businesses, groups, or multi-jurisdictional activities). Voluntary regularisation before the AEAT formally assesses a liability attracts surcharges of only 5–20% (Art. 27 LGT); discovered infractions attract sanctions of 50–150% of the unpaid amount. The conformity decision — whether to sign an acta de conformidad (30% sanction reduction, waiver of appeal) or an acta de disconformidad (full appeal rights, no reduction) — is typically the single most consequential strategic choice in the entire procedure.

Our team has defended €60M+ in tax assessments across 300+ AEAT audit procedures, with a 78% success rate. We engage from the first inspection notice and manage the full procedure — documentation strategy, voluntary regularisation analysis, conformity decision, economic-administrative claim, and judicial review — with a single integrated team.

Why the AEAT Tax Inspection is the Most Consequential Tax Procedure a Business Faces

A tax inspection differs from a limited-scope audit in two critical respects: scope and duration. The AEAT inspector has full access to all accounting records, all documents, all electronic data held by the business, and all information held by third parties — including banks, counterparties, and overseas tax authorities. The inspection can cover up to four fiscal years (the standard four-year statute of limitations) across all taxes simultaneously. The 18-month (or 27-month) duration gives the AEAT extensive time to construct an assessment from the full set of facts.

The second critical difference is the sanction exposure. A comprobación limitada that results in an assessment carries a sanction of 50–150% of the additional liability, depending on the gravity classification. For a €500,000 assessment, the sanction alone can add €250,000–€750,000. Voluntary regularisation before the AEAT makes the assessment eliminates the sanction entirely and replaces it with a 5–20% surcharge. The cost differential can exceed €700,000 in a single procedure.

Our Defence Process for AEAT Tax Inspections from First Notice to Full Resolution

From the moment the inspection initiation notice arrives, we manage the relationship with the AEAT inspector. The first step is scope analysis: which taxes, which periods, and which specific facts are under examination. We advise on what documentation to provide, in what format, and at what stage — avoiding the common mistake of providing voluntarily more than is required, which can inadvertently expand the inspection scope or create adverse admissions.

We assess exposed positions throughout the inspection and advise on the cost-benefit of voluntary regularisation versus a contested assessment. We prepare written responses to all AEAT information requests and challenges. When the inspector issues conclusions, we make the strategic conformity decision: sign the acta de conformidad to lock in the 30% sanction reduction and avoid further litigation, or sign the acta de disconformidad to preserve full appeal rights where the legal merits justify continued challenge.

For disagreement cases, we manage the complete appeal chain: reclamación económico-administrativa before the TEAR (for territorial matters under €150,000) or the TEAC (for higher-value matters or doctrine points), and recurso contencioso-administrativo in the administrative courts. Where the Tribunal Supremo’s intervention is justified under Art. 88 LJCA (contradictory TSJ rulings or unsettled Supreme Court doctrine), we escalate the case to cassation.

Regulatory Framework: Art. 150 LGT, Inspection Duration, Voluntary Regularisation, and Sanction Regime

Art. 150 LGT governs the maximum inspection duration: 18 months (general) or 27 months (complex cases). Periods attributable to taxpayer delays, third-party information requests, or judicial proceedings are excluded. Art. 27 LGT establishes the voluntary regularisation surcharge scale: 5% (within 3 months), 10% (3–6 months), 15% (6–12 months), 20% (over 12 months). Arts. 191–206 LGT establish the sanction regime: 50–100% (minor infractions), 50–150% (serious infractions). Art. 188 LGT provides the 30% sanction reduction for conformity. Art. 66 LGT establishes the four-year statute of limitations.

Real Results in AEAT Tax Audit Defence: €60M+ Defended, 78% Success Rate

• 78% success rate in AEAT tax audit defence, covering full reversals, material reductions, and successful sanction challenges.
• €60M+ in total assessed liabilities defended across 300+ procedures.
• Voluntary regularisation advice that has converted 50–150% sanction exposure into 5–20% surcharges in multiple cases.
• Strategic conformity decisions that have locked in the 30% sanction reduction and closed proceedings in cases where continued litigation was not cost-effective.
• Full appeal chain management from TEAR/TEAC to judicial review and — in relevant cases — Tribunal Supremo cassation.