What Criteria Does the Spanish Tax Authority Use to Select Taxpayers for a Tax Inspection?

What criteria does the Spanish Tax Authority use to select taxpayers for a Spanish tax inspection? In Spain, the Spanish Tax Agency (Agencia Estatal de Administración Tributaria – AEAT) does not select taxpayers for tax inspections entirely at random. Selection is primarily based on tax control plans, tax risk analysis, information obtained from third parties, and the detection of potential irregularities.

It is important to distinguish between a limited tax audit (comprobación limitada), a data verification procedure (verificación de datos), and a formal tax inspection (inspección tributaria), as these procedures differ in scope and in the powers available to the Tax Authority.

1. The Main Criteria Used to Select Taxpayers for a Spanish Tax Inspection

The guidelines set out in the AEAT’s Annual Tax and Customs Control Plan for 2026, published in the Spanish Official State Gazette (Boletín Oficial del Estado – BOE) on 12 March 2026, identify the main areas of tax risk used by the Tax Authority to direct its control activities.

A. Inconsistencies Between Income, Assets and Standard of Living

One of the most relevant criteria is the existence of discrepancies between declared income and a taxpayer’s actual financial circumstances.

The Tax Authority may analyse, among other things:

The acquisition of real estate, high-value vehicles and other expensive assets.
Bank transactions and incoming funds that do not appear consistent with declared income.
Increases in wealth without a sufficiently documented source of funding.
Personal expenditure compared with declared income.
Receipt of funds from abroad.

A discrepancy does not necessarily imply tax fraud, but it may justify an enquiry if the Tax Authority identifies a potential tax risk.

B. Use of Companies to Reduce Taxation Improperly

The Tax Inspectorate pays particular attention to corporate structures that may be used to conceal income or obtain tax advantages contrary to applicable legislation.

Situations that may be examined include:

Professionals invoicing for their services through a company where there are doubts about whether the income has been correctly attributed.
Personal expenses recorded as business expenses.
Private use of company-owned properties, vehicles or other assets.
Transactions between related companies, or between a company and its shareholders, that are not carried out on arm’s-length terms.
Companies with little or no genuine economic activity that are used to channel income or assets.

Using a company to conduct a business activity is entirely legitimate. The risk arises when the corporate structure does not reflect the actual transactions or is used to obtain an improper tax advantage.

C. Business Activities and Self-Employed Professionals

The AEAT also selects companies, self-employed individuals and professionals for inspection based on risk indicators associated with their business activities.

Particular attention may be paid to:

Declared income that is lower than the amounts indicated by the information available to the Tax Authority.
Inconsistencies between VAT, Personal Income Tax (IRPF) and Corporate Income Tax returns.
Discrepancies between invoiced revenue, bank receipts and recorded expenses.
Deduction of expenses that do not appear to be related to the business activity.
Differences between the information declared by the taxpayer and information provided by customers, suppliers or other entities.

In 2026, the control plan continues to focus on undeclared income, e-commerce, and the real estate and construction sectors.

D. International Transactions and Tax Residence

Cross-border transactions are another priority area for tax control. This is particularly relevant to individuals and businesses with financial interests in more than one country, including expatriates living in Spain.

The Tax Authority may investigate, for example:

Individuals claiming to be non-residents in Spain where there are indications that they may maintain their tax residence in Spain.
Foreign income or assets that have not been declared despite a legal obligation to do so.
Transactions between companies located in different countries.
International structures that raise questions about the effective taxation of their income.
Taxpayers paying Spanish Non-Resident Income Tax (IRNR) where there are indications that they should instead be taxed in Spain on their worldwide income.

The AEAT may use information obtained through international cooperation and tax information exchange mechanisms.

E. Large Companies, Tax Groups and Specific Sectors

The 2026 Tax Control Plan strengthens oversight of large companies, tax groups, individuals with significant assets, and complex corporate structures.

It also addresses risks associated with international transactions, VAT and Corporate Income Tax.

This does not mean that small businesses and individuals are excluded from inspections. Rather, the Tax Inspectorate allocates its resources according to the nature and complexity of the risks identified.

2. How Does the Spanish Tax Authority Identify These Risks?

The selection of taxpayers for a Spanish tax inspection does not depend exclusively on a complaint or on a previously identified tax breach. The AEAT has access to information from various sources and analyses it to identify potential tax risks.

Relevant sources may include:

Tax returns submitted by the taxpayer.
Information provided by banks, companies, customers, suppliers and other third parties, within the scope of their respective legal reporting obligations.
Available cadastral, land registry and asset information.
Information obtained through international data exchange.
Tax history and discrepancies identified during previous checks.
Requests for information issued under the legal powers granted to the Tax Authority.

The 2026 plan expressly provides for improving the quality of available information and using data analysis to select taxpayers and determine the most appropriate type of control action.

3. Is There a Minimum Amount That Triggers a Spanish Tax Inspection?

There is no general minimum threshold for income, assets or tax liability that guarantees a taxpayer will not be inspected.

Having a high income does not automatically mean that a tax inspection will take place. Selection depends on the assessment of tax risk, the taxpayer’s circumstances and the control objectives established for each financial year.

Similarly, an error in a tax return may lead to a check without necessarily resulting in a full tax inspection.

4. Can You Find Out Why the Tax Authority Selected a Taxpayer?

The specific reasons for selecting a taxpayer are not always disclosed. The Tax Authority publishes its general enforcement priorities, but it does not necessarily make public all the operational parameters used to identify potential risks.

It is also important to distinguish between the following procedures:

Request for information: A request for data or documents that does not, by itself, mean that a tax inspection has been opened.
Data verification procedure (verificación de datos): A procedure used to clarify certain errors or discrepancies in tax declarations.
Limited tax audit (comprobación limitada): A procedure designed to verify specific aspects of a tax liability.
Formal tax inspection (inspección tributaria): A procedure that may cover a broader examination and involves the specific powers provided for by law.

Therefore, receiving a notification from the Tax Authority does not necessarily mean that tax fraud is suspected. The nature of the notification, its scope and the procedure identified in it are essential when assessing the situation.

5. Conclusion: Understanding Spanish Tax Inspection Criteria

The criteria used by the Spanish Tax Inspectorate are fundamentally based on tax risk analysis. Discrepancies between assets and income, corporate structures, business activities involving potentially undeclared income, and international transactions are among the priority areas identified in the 2026 Tax Control Plan.

The official reference for reviewing the priorities for this year is the Resolution of 11 March 2026, published in the Spanish Official State Gazette (BOE).

For businesses, self-employed professionals and individuals, understanding these risk indicators can help identify potential tax exposure, improve compliance and reduce the likelihood of errors or disputes with the Tax Authority.

Anyone receiving a notification relating to a Spanish tax inspection should carefully review the nature of the procedure and consider obtaining professional tax advice to understand their obligations, rights and applicable deadlines.

Professional Tax Advice from Impley International Tax & Law

Understanding your tax obligations in Spain is essential, whether you are an individual taxpayer, a self-employed professional or a business owner. With increasingly sophisticated tax controls and information-sharing procedures, obtaining professional advice can help you remain compliant and avoid unnecessary complications.

Impley International Tax & Law, based in Jávea on the Costa Blanca, provides professional tax, accounting and legal advice to individuals and businesses, including clients with international interests.

Whether you have questions about your Spanish tax obligations, require assistance with tax planning or need guidance concerning a notification from the Spanish Tax Authority, the experienced team at Impley can help you understand your position and the appropriate next steps.

For professional advice tailored to your circumstances, visit www.impley.com or call +34 965 854 423