Four day work week in Portugal: what the law allows

Working Monday to Thursday and taking Friday, Saturday and Sunday off, with no pay cut? It is legal in Portugal and it is called the concentrated schedule (Art. 209 of the Labour Code, "horário concentrado" in Portuguese): the same weekly hours, compressed into fewer days, with each day allowed to stretch up to 12 hours. It can only be born from an agreement between you and the company or from a collective agreement. Imposed unilaterally, it is not valid.

The same 40 hours, in 4 days

Rita works in a warehouse near Leiria, 40 hours per week. The company offered her a deal: 10 hours per day, Monday to Thursday, with Friday, Saturday and Sunday free. Rita accepted and signed. Her salary did not move: she works the same 40 hours, just packed into 4 days. This is the concentrated schedule of Art. 209: the normal daily working period may increase by up to 4 hours in order to concentrate the normal weekly period into at most 4 working days (no. 1, point a).

Get the mechanics right: the law touches the day, not the week. Your daily cap goes from 8 up to 12 hours; the weekly total stays whatever your contract says, as a rule 40 hours. That is why 4x10 is the classic model: 4 days times 10 hours equals 40. Unequal days also work (12 + 12 + 12 + 4, for example), as long as the total holds.

Do not confuse it with two neighbours:

• Working time adaptability, the flexibility regime: longer and shorter weeks, evened out by averages over a reference period. The concentrated schedule is fixed, the same days every week. And the law forbids combining the two regimes (more on that below).
• Part-time work: fewer hours and proportional pay. Under a concentrated schedule you work full time; only the layout of the days changes.

The "4 day week" and the concentrated schedule: what is the difference?

When the news talks about the 4 day week, it almost always means cutting hours: working 32 or 36 hours per week for the same pay. That is not in the Portuguese Labour Code: no rule gives you the right to demand a 32 hour week on full salary. It only happens if the company agrees to it or a collective agreement provides for it.

What the law gives any worker and company, today, is something else: compression. The same 40 hours, in fewer days, with longer days. Less glamorous than the version in the news, but in force and within reach of a simple agreement.

The two routes of Art. 209

Route 1: agreement or collective agreement, at most 4 working days (point a). This is Rita's route: it is born from an agreement between worker and employer, or from a collective bargaining instrument. The law does not require written form for the agreement, but always get it on paper with the concrete design of the schedule: that is your proof of what was agreed.

Route 2: collective agreement only, 3 days on, 2 days off (point b). A collective bargaining instrument may create a schedule with at most 3 consecutive working days, followed by at least 2 rest days, with the normal weekly working period respected on average over a 45 day reference period. It is the typical design of factories and continuous operations. This route cannot be agreed individually: without a collective agreement providing for it, it does not exist.

And pay under the collective routes? The collective agreement itself decides: the instrument that sets up the concentrated schedule regulates pay and the other conditions of its application (Art. 209 no. 3). If a collective agreement covers you, look for its working time chapter.

The limits that do not move

Days of 10, 11 or 12 hours do not suspend the rest of the Code:

• Rest break (Art. 213 no. 1). Never more than 5 consecutive hours of work, or 6 consecutive hours when the daily period exceeds 10 hours. On a 4x10, the day splits into 5 + break + 5, for example; on a 12 hour day, into 6 + break + 6. The break lasts between 1 and 2 hours.
• Daily rest of 11 hours (Art. 214 no. 1). Run the numbers with Marco, who accepted 12 hour days: he starts at 8:00, works 12 hours with a 1 hour lunch, and leaves at 21:00. Until 8:00 the next day there are exactly 11 hours: he complies, just barely. With a 2 hour break he would leave at 22:00 and only 10 hours would remain: unlawful.
• Weekly rest (Art. 232). At least 1 full rest day in each week. On a classic 4x10 you get 3.
• Maximum average of 48 hours (Art. 211 no. 1). Counting overtime, the weekly average cannot exceed 48 hours, measured over a reference period of 4 to 12 months.

Forbidden to combine with the flexibility regime

No. 2 of Art. 209 is a single sentence: workers under a concentrated schedule cannot simultaneously be under the adaptability (flexibility) regime. One or the other.

The reason is arithmetic: each regime on its own can already stretch the day to 12 hours, and the two combined would produce endless shifts. If your company has you on a 4x10 and invokes "flexibility" in peak weeks to stretch your days even further, it is breaking the law: since Law 13/2023, that breach is a serious administrative offence (no. 4). The ban itself has existed since 2009; what the Decent Work Agenda added was the fine.

And the extra hours of those weeks do not vanish: everything beyond your agreed concentrated schedule is overtime, with the surcharges of Art. 268.

Who can say no

• Pregnant, recently delivered and breastfeeding workers have the right to be excused from working under a concentrated schedule (Art. 58 no. 1). In case of breastfeeding, the exemption extends to either parent when the regime affects its regularity (no. 2). Breaching it is a serious administrative offence (no. 3); the remaining rights are in the maternity leave guide.
• Workers with a disability or chronic illness, including active oncological disease under treatment, are excused if the concentrated schedule could harm their health or safety at work (Art. 87 no. 1). And there is a mandatory prior step: a health exam before the schedule starts (no. 2).
• Working students are not required to work under a concentrated schedule that clashes with their class schedule or with an exam (Art. 90 no. 6). If they do work under it, they are entitled to 1 paid day off per month, counted as actual work (no. 7).
• Night workers: night work has its own averages and caps; before accepting a concentrated schedule with night shifts, read the guide on shift work and night work.

Pay, meal allowance and overtime

Your salary does not move. You work the same weekly hours; the layout changes, not the amount. The 2 extra hours of each 4x10 day are not overtime: they are part of your normal working period, just concentrated.

Your meal allowance may move. [Common interpretation: the meal allowance is paid per day actually worked, so on a 4x10 that is 4 allowances per week instead of 5, unless your contract or collective agreement says otherwise. The Labour Code does not regulate this allowance in the private sector; the contract, the collective agreement or company practice decide.] Ask in writing before you accept.

Overtime still exists. Beyond your concentrated schedule, the normal overtime regime applies: surcharges, yearly caps and compensatory rest. But mind the physics of the calendar: on a day that already holds 12 hours of work, the 11 hour daily rest (Art. 214) leaves very little room, so overtime on top of a 12 hour day hits that wall fast.

Can they impose it? Can you demand it?

Impose it, no. The individual route requires agreement: without your acceptance, and without an applicable collective agreement setting it up, the company cannot stretch your day past 8 hours through this regime. What the company can do on its own is set and change the work schedule within the normal limits, and moving you to a 4x10 without agreement does not fit there. If it happens: refuse in writing, citing Art. 209 no. 1, and see how to file a complaint with ACT.

Demand it, also no. No article gives you the right to impose a 4x10 on the company. What you can do is propose it, in writing, with the concrete design of the schedule and the upside for both sides. [It depends on the case: if you have young children or are a carer, the parental flexible working arrangements are a different route, with rules and force of their own.]

And to undo it? Art. 209 does not regulate the way back. [It depends on the case: whatever the agreement or the collective agreement says applies, such as duration, notice or a return clause. With nothing in writing, undoing it takes a new agreement.] One more reason to put the regime on paper, with a date and an exit door.

Six situations, what the law says

For employers: setting up a 4x10 without risks

If you are considering concentrated schedules, the legal basis is Art. 209 and the setup decides everything. Document the agreement with each worker: the law does not require written form, but without paper there is no proof of the schedule design or of the exit door; include days, start and end times, breaks and a reversal rule. The variant of 3 consecutive days with a 45 day average is only available through a collective bargaining instrument (point b): without an applicable agreement, do not use it. Do not combine it with the flexibility regime: the ban in no. 2 has applied since 2009 and, since Law 13/2023, it costs a serious administrative offence. Check the exemptions before applying the regime: pregnant, recently delivered and breastfeeding workers (Art. 58), workers with a disability or chronic illness with a mandatory prior health exam (Art. 87 no. 2), and working students during class hours (Art. 90 no. 6). Design the days with rest rules first: at most 6 consecutive hours on days above 10 hours, a break of 1 to 2 hours, 11 hours between working days; on a 12 hour day, only the 1 hour break makes the numbers close. Keep the schedule map and the working time records in order: that is where ACT starts. For drafting clauses in sectors with their own collective agreement, checking with a lawyer is the prudent recommendation.