Social Security in Spain has warned self-employed workers that operating without official registration can lead to fines reaching 12,000 euros.
Self-employed workers are defined as individuals who routinely carry out an economic activity on their own account and outside the management or organization of another person. When beginning professional work, individuals must officially report the activity to both the Tax Agency, known as Hacienda, and Social Security.
Workers must register in the Special Scheme for Self-Employed Workers, known as RETA. Social Security explained that RETA is the system requiring registration for anyone performing habitual, personal, and direct economic activities for profit, provided the work is not covered by an employment contract with a company.
Social Security emphasized that registration is mandatory whenever an activity is conducted on a recurring basis, even if total earnings do not reach the Interprofessional Minimum Wage, known as SMI. Low income alone does not exempt a worker from registering, as the obligation depends on whether service provision or economic activity is carried out habitually.
Fines for failure to register
Failing to comply with registration obligations carries financial penalties determined by the severity of the infraction. Minor infractions regarding registration requirements result in fines ranging from 300 euros to 6,000 euros.
Infractions classified as serious carry fines ranging from 3,750 euros to 12,000 euros. In addition to paying the fine, non-compliant workers are required to pay all back contributions for the entire period during which they carried out the undeclared activity.
Rules for late registration
Social Security has also outlined rules for regularising situations where a worker registers after starting their activity. In these cases, the reference date is fixed as the day work actually began or invoicing started, meaning late registration does not wipe out prior obligations.
For the period between the actual start of work and the end of the month in which registration is reported, contributions are calculated using the minimum base of the first section of the general table. In 2026, this minimum contribution base stands at 950.98 euros.
Social Security noted that contributions owed for this initial period have a specific rule: they are excluded from the annual regularisation process later conducted by the Treasury, known as Tesorería.
