Spain’s Tax Agency (Agencia Tributaria) has published the guidelines that will shape its fight against fraud in 2026 – and many self-employed workers (autonomos) will be under closer scrutiny.

The agency released its Annual Tax Control Plan in Spain’s official state bulletin (BOE), outlining the sectors and behaviours that inspectors will be focusing on in the coming months.

Although many measures are aimed at large companies and high-net-worth individuals, the document also includes several areas that directly affect freelancers and small businesses – particularly those where there is a higher risk of undeclared income or heavy use of cash payments.

Businesses dealing directly with consumers

As in previous years, tax inspectors will closely monitor businesses that deal directly with end consumers.

These sectors tend to involve frequent small transactions and higher cash usage, which can make it easier to conceal income.

According to tax experts, inspections traditionally focus on activities such as:

• Retail businesses
• Restaurants, bars and hospitality
• Service-sector businesses
• Real estate activities
• Home renovation and repair services
• Construction

In these industries, the volume of cash transactions or lack of clear traceability can increase the risk of undeclared economic activity.

Businesses that refuse card or bank payments

One major red flag for tax inspectors will be businesses that do not accept bank payments such as card transactions or transfers.

Tax authorities say these types of operations make it more difficult to trace economic activity and may indicate attempts to conceal income.

Inspectors will also be paying closer attention to businesses that use payment systems based abroad in order to avoid Spain’s reporting requirements.

Suspicious gaps between income and lifestyle

Another trigger for investigations will be discrepancies between a taxpayer’s declared income and their lifestyle, assets or spending levels.

According to Jose Maria Mollinedo, general secretary of Spain’s association of treasury technicians (Gestha), these inconsistencies are often a key indicator of possible tax irregularities.

‘If a taxpayer declares low income but maintains a much higher standard of living, it can trigger further investigation,’ he previously told Diario A y E.

Unusual changes in stock or business results

The Tax Agency will also monitor businesses showing unusual fluctuations in inventory levels.

Large or unexplained changes in stock can sometimes indicate undeclared sales or accounting manipulation.

Companies that report financial results that appear incompatible with the economic reality of their activity – such as businesses that declare losses year after year without clear justification – may also face closer inspection.

Authorities will also analyse cases where declared income is lower than payments reported by third parties, which could signal undeclared activity.

Software used to hide sales

Another focus will be the use of so-called ‘double-use’ accounting software.

These programmes allow businesses to alter or delete sales records in order to hide revenue from tax authorities – a practice the government has increasingly targeted in recent years.

Inspections and on-site visits will continue

Despite the increased use of data analysis and digital tools, tax authorities will continue conducting in-person visits to businesses where there are signs of irregularities.

These inspections allow officials to verify real business activity, review accounting records and check whether the company is accurately declaring its turnover.

The agency will also continue investigating networks involved in issuing false invoices, where shell companies are created to generate fake expenses that reduce another company’s tax bill.

The Tax Agency plans to expand its use of preventive alerts aimed at helping freelancers avoid mistakes in their tax returns.

These notices are sent when the agency detects possible errors or inconsistencies in a taxpayer’s declarations, allowing them to correct the issue before a formal investigation begins.

Officials say the goal is to encourage voluntary compliance and help self-employed workers align their tax behaviour with others in their sector – potentially avoiding penalties or audits.