Spain's working hours reform law, passed through 2025 and entering into force on a phased basis, establishes a maximum standard working week of 37.5 hours for all workers as a general rule. This replaces the 40-hour threshold that had been the standard since the Workers' Statute of 1980 — making it the most significant change to ordinary working time in four decades. The practical implications for employers extend well beyond arithmetic calculations of hours worked.
What Exactly Changes Under the Reform
The reform modifies Article 34 of the Workers’ Statute (Estatuto de los Trabajadores), fixing 37.5 hours per week as the maximum standard working time, calculated as effective work time on an annual basis. Collective agreements and individual contracts may set lower limits but not higher ones. Presence time that does not constitute effective work — waiting periods, stand-by arrangements outside the workplace — retains its specific treatment and does not count toward this limit.
The legislation also introduces a reinforced negotiation obligation in sectoral and company-level collective agreements to adapt irregular working time distribution to the new maximum, with a mandatory negotiation period that parties must exhaust before referring the matter to the labour authority.
Working Time Registration: Updated Obligations
Since the 2019 amendment of Article 34.9 of the Workers’ Statute, Spanish employers have been required to record each employee’s working time daily. The reduction to 37.5 hours per week requires updating registration systems to reflect the new threshold, and reviewing control mechanisms where working time is distributed irregularly across the year or where hour-banking systems are in place.
Labour inspectorate enforcement of working time records has intensified significantly in recent years. Minor infringements carry fines of €70 to €750, while serious violations — including the total absence of records or systematic under-recording — attract fines of €751 to €7,500. Beyond financial penalties, deficient time records can be used as evidence in overtime pay disputes and worker classification proceedings.
Operational Reorganisation: Shifts, On-Call Arrangements and Irregular Distribution
The move from 40 to 37.5 hours represents a reduction from approximately 1,826 to 1,712 effective working hours per year per employee — roughly 114 fewer hours annually. Organisations can manage this difference in several ways:
Irregular working time distribution. Article 34.2 of the Workers’ Statute allows companies to distribute up to 10% of annual working time irregularly through collective agreement or, in the absence of one, through agreement with employee representatives. This mechanism allows concentration of hours during peak periods offset by reductions in quieter periods, without treating the additional hours as overtime.
New shifts or additional headcount. In continuous operation sectors — hospitality, logistics, healthcare, process manufacturing — the working time reduction may require creating new shifts or increasing headcount to maintain operational coverage. Calculating minimum staffing requirements per shift and costing additional coverage must be completed before the reform takes effect.
Remote work and flexible scheduling. For companies with a high proportion of remote workers, the reduction can be implemented through greater daily scheduling flexibility, provided adequate availability is maintained and working time is properly recorded.
Remuneration Structure: Which Supplements Are Affected
Working time and pay are closely linked in most contracts and collective agreements. The working time reduction does not automatically reduce salaries — hourly pay effectively increases — but it does have consequences for certain supplements and allowances:
Convention-based allowances calculated on a specific number of hours must be reviewed. Availability supplements and on-call or public holiday pay arrangements may need recalibrating. Overtime, whose activation threshold drops with the lower ordinary hours limit, will statistically increase unless working time organisation is adapted.
A remuneration structure audit before implementation is essential to identify which salary components are affected by the change in the ordinary working time limit and to quantify the total cost impact.
Interaction With Existing Collective Agreements
Collective agreements establishing working weeks above 37.5 hours are modified by operation of law from the reform’s entry into force. However, agreements that had already negotiated lower limits — common in large corporations and sectors such as banking, insurance, and the public administration — are unaffected beyond confirmation that they already meet the new legal standard.
Negotiations for new collective agreements will necessarily use the new maximum as their starting point. Bargaining tables now have the opportunity to negotiate not just the quantum of hours, but their distribution, flexibility mechanisms, and the compensation framework within the new framework.
At BMC, we guide companies through the adaptation of their employment structures to the new working time framework. Discover our employment law services.
Regulatory Framework: Key Legal Instruments of the 37.5-Hour Working Week Reform
The reduction of the maximum working week to 37.5 hours is grounded in a specific legislative framework that establishes both the obligation and the enforcement mechanisms.
Real Decreto Legislativo 2/2015, de 23 de octubre (Estatuto de los Trabajadores — ET), Article 34: This is the primary statutory provision governing working time. Before the reform, Article 34.1 ET set the annual ordinary working time at 1,826 hours, equivalent to 40 hours per week. The reform amends this provision to set the new annual limit at approximately 1,712 hours (37.5 hours × 45.65 effective working weeks per year, after accounting for rest periods). The article also governs the distribution of working time, establishing minimum daily and weekly rest periods that constrain how the 37.5 hours can be allocated across the working week or annualised through irregular distribution agreements.
Real Decreto 1561/1995, de 21 de septiembre, on special working hours: This decree governs special working hour arrangements in sectors with particular characteristics (night workers, seasonal workers, transport, hospitality, healthcare). The reform interacts with this decree because sector-specific working time rules — which may allow working time to be averaged over longer reference periods — must be re-evaluated in light of the new 37.5-hour baseline. Companies in affected sectors will need to verify whether their existing special arrangements remain within the reformed statutory framework.
Real Decreto 902/2020 on pay equity and Real Decreto 901/2020 on equality plans: These instruments become newly relevant in the context of the working time reform because the reform requires digital, verifiable time records for all workers. The time-recording obligation interacts with pay equity obligations: companies must now be able to demonstrate that actual hours worked by female and male employees within the same job classification are accurately recorded and that compensation structures do not create indirect gender-based differentials through differential application of overtime or irregular time distribution arrangements.
Real Decreto Legislativo 5/2000, de 4 de agosto (LISOS): The sanctions for violation of working time obligations — including the digital time-recording requirement — are classified under the LISOS as serious infractions (per-worker fines of up to €7,500) or very serious infractions when systematic violation is detected or when the employer retaliates against workers who assert their time-recording rights.
Understanding this regulatory framework is essential for correctly configuring time-recording systems and assessing the compliance risk of existing working time arrangements. For companies that have relied on annual hour averaging — whether through collective agreement or individual pact — the key question is whether the averaged arrangements produce a weekly average at or below 37.5 hours when calculated over the reference period. If not, the arrangement must be renegotiated. Companies in this position should prioritise a working time audit before the reform’s enforcement date to avoid being caught with non-compliant arrangements during an Inspectorate visit.
