They are confused all the time because both «trim» your working day when you have a child, but they are not the same. Nursing leave (permiso de lactancia) is a short leave designed for the baby that normally does not cut your pay. Reduced hours for legal guardianship (guarda legal) last until the child is 12 and do cut it. Here is how they differ; the full pay table for guardianship is in reduced working hours for childcare, so we do not repeat it here.

The differences in one table

Point Nursing leave (art. 37.4) Legal guardianship (art. 37.6)
Who Workers in cases of birth, adoption, fostering with a view to adoption or foster care Anyone who directly cares for a child under 12 or a person with a disability who does not work
Until when Baby is 9 months (12 if both use it with the same duration and system) Child is 12
How much 1 hour a day, divisible in two Between 1/8 and half of the daily working day
Alternatives Half an hour of reduced hours or accumulation into full days Not as a general rule: accumulation into full days is only provided for, if the agreement sets it, for a child with cancer or serious illness
Pay No cut provided for the 9 months; proportional cut from month 9 to 12 if extended Proportional reduction
Notice 15 days or what the agreement sets 15 days or what the agreement sets

For multiple births, adoptions, fostering placements or foster care, nursing leave increases proportionally.

Nursing leave in detail

Article 37.4 gives one hour of absence that you can divide into two parts. There are three ways to use it:

  1. One hour, whole or in two parts.
  2. Half an hour of reduced hours, if you prefer to swap it.
  3. Accumulate it into full days, to add to your birth leave. The Statute does not say how many days result: it depends on the convenio colectivo (collective agreement) or an agreement with the employer.

It is an individual right of each worker. If both parents use it with the same duration and system, it can be extended until the baby is 12 months old, with a proportional pay cut from 9 months.

An example. Raquel works 8 hours a day and earns €1,800 gross a month. Her baby is born on 10 March 2026 and she and her partner both claim nursing leave with the same duration and system:

Period What she takes Pay
Until 10 December 2026 (9 months) 1 hour a day €1,800 a month, no cut provided
10 December to 10 March 2027 1 hour a day 1/8 less: 1,800 × 7/8 = €1,575 a month
Total lost in those 3 months 225 × 3 €675 gross

That is the law’s arithmetic; your payslip may have supplements that change the calculation, so check your agreement.

Article 37.6 gives a reduction of the daily working day of between one eighth and half, with a proportional pay cut, to anyone directly caring for a child under 12 or a person with a disability who does not perform paid work, or who must care for a relative up to second degree who cannot look after themselves. With 8 hours, one eighth is 1 hour and half is 4. The pay figures are in the article linked above.

There are special cases in 37.6: a reduction of at least half to care for a child with cancer or another serious illness during hospital admission and treatment, or extension beyond age 12 where severe disability or dependency is proven.

Premature or hospitalised babies

Article 37.5 is a third right: one hour of absence if the baby is born prematurely or must stay in hospital after the birth, plus a reduction of up to two hours a day with a proportional pay cut.

Who sets the schedule and what if you disagree

Under article 37.7, setting the hours is for the worker, within their ordinary working day. For guardianship the agreement may set criteria to reconcile your rights with the company’s needs. You must give 15 days’ notice, or whatever the agreement says, stating start and end dates. Disputes are resolved by the labour court under the procedure of article 139 of the procedural law.

Requesting any of these leaves protects you against dismissal: dismissing someone who has requested or is taking them is void (art. 55.5.b). Check the deadlines in how long you have to challenge a dismissal.

How to choose between an hour, half an hour or full days

There is no best option for everyone. The daily hour gives you room every day: starting later, leaving earlier or splitting it in two. The half-hour reduction is the same idea with less time, useful if your job leaves no gaps. Accumulating it into full days adds whole days to your birth leave and often suits people who live far from work, but it depends on your collective agreement: read what it says, because it may set the number of days and the conditions.

If the other parent also uses it with the same duration and system, you can both reach the baby’s 12 months, accepting the proportional pay cut from the ninth month.

Why your case may be different

  • Your collective agreement may improve nursing leave: more accumulated days, or a longer period. Ask for it in writing.
  • If you have already used up your birth leave, see how it fits with the weeks of birth leave.
  • The public sector has its own rules (the Basic Statute of Public Employees), with rules that differ from this article.
  • If nursing leave does not fit your shift, a working-time adaptation under article 34.8 is another tool; see how to request one.

On contributions, article 237.3 of the Social Security Act raises contributions to 100% during the first three years of reduced hours to care for a child, for retirement, permanent incapacity and other benefits. It does the same for the nursing-leave reduction in the last paragraph of 37.4, for several benefits.

If you need time away from work, compare this option with voluntary leave of absence in Spain, particularly the rules on returning.

This is general information. With deadlines or money at stake, speak to an employment lawyer (abogado laboralista) or a union.