Brazil’s National Confederation of Commerce of Goods, Services and Tourism (CNC) has filed a direct action of unconstitutionality with the Supreme Federal Court, seeking to delay the end of the 6x1 work schedule until December 2027. The schedule involves six days of work followed by one day of rest.

The constitutional amendment provides for a 5x2 schedule, with two days of paid weekly rest. It also reduces the maximum working week from 44 to 42 hours from December 16 this year, with a further reduction to 40 hours. The CNC is asking the court to move the introduction of the 42-hour week and the new schedule to December 16, 2027, and to postpone the later 40-hour phase until December 2028. Under the current timetable, the final reduction is due in December 2027.

The confederation says it does not oppose ending the 6x1 schedule. Its challenge argues that the amendment changes constitutional rules governing labor relations in a way that may conflict with existing constitutional protections, including collective bargaining, legal certainty and legitimate expectations.

The CNC is seeking an interim ruling from a single justice to suspend the 2026 implementation. It also wants collective agreements and conventions that currently provide for the existing schedule to remain in force, rather than being invalidated after the 60-day period set out in the amendment.

Other provisions challenged by the group concern the role of union negotiations in implementing the new schedule, different treatment for micro and small businesses, a transition period of up to one year for companies holding public-sector contracts, and the exclusion of public servants from rules on working-time controls for so-called “super-employees.”

The CNC argues that working-hour provisions in collective agreements cannot be separated from related terms, such as shift patterns, compensation arrangements, additional pay and staffing. It says changing those provisions individually could unsettle the balance of agreements negotiated between employers and unions. The filing also argues that agreements should not be altered during their term, even through collective bargaining.

Labor lawyer Antonio Galvão Peres said a constitutional amendment may be unconstitutional if it violates a protected clause of the Constitution. He argued that the measure could restrict freedom of association and collective bargaining, and said a collective agreement may qualify as a perfected legal act. He also cited equality and equal-treatment principles.

A survey of 37,000 negotiations conducted between July 2024 and July 2025 found that 81% included working-hours clauses, with an average of five such provisions per agreement, according to Hélio Zylberstajn, a senior professor at the University of São Paulo and economist responsible for Fipe’s Salariômetro.

Eduardo Gomes Gaelzer, a lawyer and researcher at the University of São Paulo’s Getrab labor-law study group, raised a separate concern about the transition to a 42-hour week without collective bargaining. Workers currently scheduled for six days could lose Saturday shifts, with those hours redistributed across the week rather than paid as overtime, he said. He argued that compensation mechanisms alone would not settle whether the amendment’s arrangement of weekly hours and rest days is compatible with constitutional limits.

Sources: Folha Mercado.