Children have the same rights regardless of whether their parents are married
One of the most common concerns among unmarried couples going through a separation is what will happen to their children. If we are not married, do our children have fewer rights? The answer is clear and unequivocal: no. The Spanish Constitution, in Article 39.2, establishes that public authorities guarantee the full protection of children, who are equal before the law regardless of their parentage. This means that, legally speaking, children of an unmarried couple have exactly the same rights as children of a married couple.
That said, while children's rights are identical, the separation process has practical differences that are worth understanding. There is no divorce because there is no marriage (if you are married, see our guide on express divorce in Spain), but a custody arrangement, child support, and use of the family home must still be established. According to INE data, more than 180,000 children are born outside of marriage in Spain every year — nearly half of all births — making it essential to understand the available options.
Children of unmarried couples have exactly the same rights as children of married couples. The Spanish Constitution guarantees equality for all children regardless of their parentage.
Parental authority and parentage: the starting point
Parentage determines rights
For a child to have rights in relation to both parents, legal parentage must first be established. In the case of the mother, parentage is determined by birth. In the case of the father, the situation depends on whether he has formally acknowledged the child.
When both parents go together to the Registro Civil to register a newborn, the father completes the acknowledgment at that same time. This is the most common and straightforward scenario. If the father has not acknowledged the child, a parentage recognition procedure will be required — which may be voluntary or court-ordered — before any custody arrangement can be claimed or established.
Once parentage is established with respect to both parents, parental authority (patria potestad) is shared automatically. It does not matter whether the parents are married, in a registered civil partnership, in an unregistered relationship, or simply two people who had a child together. Shared parental authority means that both parents have equal rights and obligations regarding their minor children: education, healthcare, legal representation, management of their assets, and of course custody.
Registered civil partnership vs. unregistered relationship
In Spain, unmarried couples may register as a pareja de hecho (civil partnership) with regional or municipal registries, which grants certain rights to the couple. However, for the purposes of children, being registered or not is irrelevant. The distinction affects matters such as compensatory support, inheritance rights, or tax benefits between the partners themselves, but never custody, child support, or visitation arrangements. These are governed exclusively by the best interests of the child.
How child custody is determined
The same criteria as in divorce
When an unmarried couple with children separates, custody is determined using exactly the same criteria as in a divorce. The judge weighs the best interests of the child, taking into account factors such as:
- Each parent's relationship with the children: Who has been the primary caregiver, who takes the children to school, who attends parent-teacher meetings, who manages medical appointments.
- Availability: Each parent's working hours and their actual capacity to devote time to childcare.
- Stability of the environment: Housing, neighbourhood, proximity to school, each parent's family support network.
- The child's wishes: From the age of 12 — and in some cases earlier, if the child is sufficiently mature — the judge will hear the child's opinion, although it is not binding.
- Parents' ability to cooperate: Each parent's willingness to support the child's relationship with the other parent.
The trend in Spain is clearly in favour of shared custody when both parents are capable and circumstances allow. According to the Consejo General del Poder Judicial (CGPJ), in 2024 shared custody was awarded in 43.2% of proceedings involving minor children, a figure that has grown steadily over the past decade.
Two routes for establishing arrangements
Unlike divorce, where custody is necessarily established within the judicial marriage dissolution proceedings, unmarried couples have two possible paths.
Agreement between the parents. If both parents agree, they can draw up a parenting plan covering custody, a schedule of residency, child support, and use of the family home. If reaching an agreement is difficult, family mediation is a highly effective tool for breaking through negotiating impasses. This agreement must be submitted to the family court for approval. Once approved by the court, it carries the same legal force as a divorce judgment.
Contested judicial proceedings. If no agreement is reached, either parent may file an application for parental measures (medidas paterno-filiales) before the family court. The process is similar to a contested divorce: filing, response, evidence, a possible report from the psychosocial assessment team, and a judgment. Even though there is no marriage to dissolve, the measures are processed with the same procedural safeguards.
Child support: the same obligation as in marriage
The obligation to contribute to children's support does not depend in any way on whether the parents are or were married. Article 143 of the Código Civil establishes the obligation to provide maintenance to children without distinguishing between marital and non-marital parentage. This covers food, housing, clothing, medical care, and education.
Child support is calculated based on the income of both parents and the needs of the child, applying the same criteria and guidelines as in divorces. In practice, this means that the non-custodial parent — or the parent with the greater earning capacity in shared custody arrangements — must pay a monthly amount to cover the child's ordinary expenses.
In addition to the monthly payment, both parents must contribute to extraordinary expenses: extracurricular activities, medical treatments not covered by public healthcare, special school supplies, and so on. The customary split is set in proportion to each parent's income, generally 50/50 or in proportion to their respective financial capacities.
Key difference: no automatic compensatory support
One important difference between the separation of an unmarried couple and a divorce is that, in principle, there is no automatic right to compensatory support between the partners. In a divorce, if one spouse has suffered an economic imbalance as a result of having dedicated themselves to caring for the home and children, they may claim compensatory support from the other. For unmarried couples, this right depends on the applicable regional legislation and case law, and is not always recognised.
This difference, however, only affects the economic relationship between the parents as a couple. The children's economic rights — child support and contribution to expenses — are exactly the same.
The parenting agreement without marriage
Although a formal divorce settlement agreement is typically associated with marriage, unmarried couples can and should formalise an equivalent agreement when they separate. This document — which some courts refer to as a parental measures agreement — should include:
- The custody arrangement: shared or sole.
- A detailed residency schedule, including regular days, weekends, holidays, and public holidays.
- Child support payments and contributions to extraordinary expenses.
- Use of the family home, which is generally assigned to the custodial parent regardless of who owns it.
- The contact arrangement for the parent who is not with the children at any given time.
Drafting this parenting agreement with precision is essential. Vague or informal agreements are a source of future conflict. And once approved by the court, failing to comply with it carries the same legal consequences as breaching a divorce judgment.
Even though there is no marriage to dissolve, it is essential to formalise measures regarding children through the courts. A verbal agreement between parents has no legal force and leaves children unprotected.
Common mistakes unmarried couples make when separating
Many unmarried couples make avoidable mistakes when separating, precisely because they do not realise that the legal mechanisms protecting children are equally available to them.
Not formalising arrangements through the courts. The most serious and most common mistake. Many unmarried couples agree on custody and expenses verbally. While the relationship remains amicable, this works well enough. But when disagreements arise, there is nothing to fall back on legally. Either parent can unilaterally change the terms because there is no court order requiring compliance.
Believing the father has no rights because he is not married to the mother. As long as parentage is established, the father has exactly the same rights as in a marriage. Parental authority is shared and custody is determined based on the child's best interests, not the parents' marital status.
Not documenting agreements and communication. When there are no formal court proceedings, communication between parents about custody tends to be informal: WhatsApp messages, phone calls, verbal agreements. If things become complicated, reconstructing who said what and what was agreed is virtually impossible. Using a tool like Niddo to centralise communications and custody agreements provides an organised record that can prove decisive if matters reach the courts.
Not registering the civil partnership when it would be beneficial. Although registration does not affect children's rights, it can have tax and social protection implications for the parents themselves. Consulting a lawyer about whether registering as a pareja de hecho is advisable is recommended before problems arise.
Your children are protected by law
Separating as an unmarried couple with children can be just as emotionally complex as a divorce, but children's rights are equally protected under Spanish law. Do not let the absence of a marriage certificate lead you to believe that your children — or you — have fewer rights or fewer options.
Formalise the arrangements through the courts, seek legal advice if you need it, and organise co-parenting with tools that facilitate communication and reduce conflict. Your children deserve the same stability and protection as any other child, and the law guarantees exactly that.
If you are going through a separation and need to organise custody, a residency schedule, and shared expenses in a clear and documented way, download Niddo for free and start managing your co-parenting with a tool designed to protect what matters most.
