Changing from Sole to Joint Custody in Spain: A Guide for Expats

🇪🇸 Read the original in Spanish

The family model in Spain has undergone a profound transformation in recent decades, consolidating joint custody not as an exception, but as the preferred and most beneficial option for minors. Many parents who once signed a regulatory agreement establishing sole custody (usually maternal) now wonder if it is possible to modify that situation to become involved on equal terms in raising their children. The answer is yes: the Spanish legal system allows for the transition from a sole custody model to a joint one, provided that strict legal requirements are met and it is proven that the change serves the best interests of the minor. Below, we analyse this process in depth, including its procedures, costs, and the keys to ensuring a successful application.

The Legal Framework: What Do the Civil Code and Spanish Jurisprudence Say?

The regulatory framework governing the modification of custody measures is based on the Código Civil (Civil Code), which was thoroughly reformed by Ley 15/2005, de 8 de julio (Law 15/2005 of July 8), expressly introducing joint custody into Spanish common law.

The cornerstone of this entire process is found in *Article 90.3 of the Código Civil**, which establishes that measures ordered by a judge or agreed upon in a convenio regulador (regulatory agreement/settlement agreement) may be modified when advised by the new needs of the children or a change in the parents' circumstances. For this change to succeed, the jurisprudence of the Tribunal Supremo* (Supreme Court) requires that the alteration of circumstances be "substantial", "unforeseen", "permanent", and not voluntarily brought about to evade obligations.

For its part, *Article 92 of the Código Civil** regulates the granting of joint custody. This article determines that it will be granted when requested by the parents in the convenio regulador* or when they reach this agreement during the proceedings. Paragraph 8 of this article exceptionally allows the judge, at the request of one of the parties, to order joint custody even without the agreement of both parents, provided that the minor's interests are protected.

The Absolute Limit: Gender Violence

It is essential to take into account the restrictions imposed by Ley Orgánica 1/2004, de 28 de diciembre, de Medidas de Protección Integral contra la Violencia de Género (Organic Law 1/2004 on Integrated Protection Measures against Gender Violence). *Article 92.7 of the Código Civil*** is categorical: joint custody will not be established—nor will sole custody be maintained—if either parent is involved in ongoing criminal proceedings initiated for attempting against the life, physical integrity, liberty, moral integrity, or sexual freedom and indemnity of the other spouse or the children living with both. Nor will it proceed if the judge detects well-founded evidence of domestic or gender violence.

Requirements to Request a Change to Joint Custody

For a family court to agree to modify an established sole custody arrangement and transform it into joint custody, the requesting parent must prove that a series of objective requirements are met:

• Substantial change in circumstances: It must be proven that the situation of the parents or the children has changed significantly since the first agreement was signed or the divorce ruling was issued. Examples of this include a change in work schedules allowing for a better work-life balance, the children growing older (demanding a greater presence of both parents), or a change of residence that brings the parents' homes closer together.
• The best interest of the minor: This is the governing principle of family law in Spain (el interés superior del menor). The goal is not the benefit or convenience of the parents, but the well-being of the minor. The child's emotional stability, school and social roots, and their own opinion if they have sufficient maturity (it is mandatory to hear them if they are 12 years old or older) will be evaluated.
• A minimum level of respect between the parents: Although a perfect friendship is not required, the Tribunal Supremo has reiterated that a level of communication and mutual respect is necessary to coordinate daily decisions regarding the minor's life (school, doctors, extracurricular activities).
• Proximity of residences: For joint custody to be viable and not subject the minor to unnecessary stress, the residences of both parents must be within a reasonable distance that allows them to maintain the same school and social environment without exhausting commutes.

Practical Step-by-Step Steps to Switch to Joint Custody

The procedure for requesting a modification of measures will depend on whether there is an agreement between both parents or if, on the contrary, it is a contentious application.

Mutual Agreement Route (The Fast and Economical Route)

If both parents agree to make the transition to joint custody, the process is simple and fast:

1. *Drafting a proposal for a Convenio Regulador de Modificación de Medidas (Regulatory Agreement for the Modification of Measures):* A lawyer will draft a new agreement detailing the division of time (alternate weeks, fortnights, etc.), the use of the family home, contributions to the children's expenses, and the communication regime.
2. Filing the mutual agreement lawsuit: The lawsuit is filed before the Juzgado de Primera Instancia (Court of First Instance) that issued the initial ruling, accompanied by the new agreement signed by both parties.
3. Judicial ratification: Both parents must appear at court to ratify (sign) the agreement before the Letrado de la Administración de Justicia (Court Clerk, formerly known as the secretario judicial).
4. *Report from the Ministerio Fiscal (Public Prosecutor's Office):* The prosecutor will review the agreement to ensure it is not detrimental to the minors.
5. *Court approval ruling (Sentencia de homologación):* The judge will issue a ruling approving the new agreement, which will replace the previous one.

Contentious Route (Without Agreement Between the Parents)

If one of the parents opposes the change, a contentious judicial modification procedure must be initiated:

1. Filing a contentious lawsuit for the modification of measures: The interested parent, assisted by an abogado (lawyer) and a procurador (court representative), files a lawsuit before the competent court, detailing the change of circumstances and providing all evidence justifying that joint custody is best for the minor.
2. Response to the lawsuit: The other parent has a period of 20 business days (días hábiles) to oppose the lawsuit and present their arguments and evidence.
3. *The court hearing (Vista de juicio): The parties are summoned to a hearing where evidence will be presented: questioning of the parents, witness testimonies, and, if applicable, the hearing of the minor (exploración del menor*).
4. *The report from the Gabinete Psicosocial (Psychosocial Team): In most contentious proceedings, the judge or the Ministerio Fiscal* will request the intervention of the psychosocial team attached to the court (psychologists and social workers). These professionals will conduct interviews with the parents and children and issue a report (non-binding, but carrying enormous weight with the judge) recommending or advising against joint custody.
5. *Ruling (Sentencia): The judge will issue a ruling granting or dismissing the modification of measures. An appeal (recurso de apelación) can be filed before the corresponding Audiencia Provincial* (Provincial High Court) within a period of 20 business days.

Deadlines, Costs, and Key Figures of the Process

Approaching a judicial process requires knowing beforehand the approximate times and economic costs involved in the Spanish judicial system:

• Average resolution time by mutual agreement: Between 2 and 4 months, depending on the workload of the court.
• Average resolution time via the contentious route: Between 8 and 18 months. This period can be extended if the waiting list for the court's Gabinete Psicosocial evaluation is long (in some provincial capitals, the delay for this report exceeds 6 months).
• Key age of the minor: From the age of 12 (or earlier if they have sufficient maturity), the minor has the legal right to be heard by the judge and prosecutor in the so-called exploración del menor (hearing of the minor).
• Cost by mutual agreement: By sharing a lawyer and a procurador, the total cost usually ranges between 600 € and 1,200 € (to be split between both).
• Cost via the contentious route: Each party must hire their own lawyer and procurador. The fees of a family law specialist lawyer for a contentious process usually range between 1,500 € and 3,500 €, to which must be added the fees of the procurador (around 200 € - 400 €) and, if hired privately, an external psychological expert report which can cost between 800 € and 1,800 €.

Concrete Examples of Modification of Measures

To understand how a change in custody affects the family economy and daily logistics, we analyse two common scenarios:

Example 1: The Impact on Child Support and Housing

> Carlos and Sofía divorced in 2020. Sole custody was established for Sofía. Carlos paid child support (pensión de alimentos) of 350 € per month for their 6-year-old son, and Sofía had the use of the family home. In 2024, Carlos secured a 100% remote working contract and lives just 2 kilometres from the child's school. He requests joint custody on alternate weeks. > > Upon granting joint custody, the judge determines that, since both parents have similar incomes (about 1,800 € net per month each), the child support payment of 350 € is terminated. Instead, a joint account is opened where each will deposit 150 € per month for school, medical, and clothing expenses for the minor. Likewise, as the exclusive use of the home due to sole custody is terminated, the sale of the shared property or a temporary, time-limited allocation of its use is agreed upon, forcing a financial reorganisation for both parties.

Example 2: Parents with Disparate Incomes

> María and Javier have a 9-year-old daughter. After their divorce, maternal sole custody was established. Javier requests a modification to joint custody after a change in his work shift allows him to have afternoons free. Javier earns a net salary of 3,200 € per month, while María works part-time and earns 950 € net per month. > > The court grants joint custody because it benefits the minor. However, to avoid an economic imbalance that would harm the child's standard of living when she is with her mother, the judge rules that Javier must pay a compensatory child support pension of 250 € per month while the child is under María's care, in addition to covering 70% of extraordinary expenses (compared to the 30% that María will assume). Joint custody does not always exempt a parent from paying child support if there is a significant wage gap between them.

Mistakes You Must Avoid

Initiating a modification of measures without the right strategy can lead the process to failure and prolong family conflict. Avoid making these mistakes:

• Requesting the change for strictly financial reasons: Judges quickly detect when a parent requests joint custody solely to stop paying child support or to regain use of the family home. The request must always centre on the well-being of the minor and your actual availability to raise them.
• Failing to provide proof of the change in circumstances: It is not enough to say that you now have more free time or that your child is older. You must provide employment contracts, work schedules signed by your company, proof of your new residence near the school, or reports proving your prior involvement in the child's activities.
• Using the minor as a messenger or witness: Trying to influence the minor's opinion so they tell the judge they want to spend equal time with both parents usually backfires. The psychologists of the Gabinete Psicosocial easily detect parental alienation or manipulation, which will destroy your chances of obtaining custody.
• Starting a contentious process without trying mediation first: Except in cases of gender violence, going straight to aggressive court proceedings without having attempted an amicable approach or formal negotiation through lawyers or mediators usually hardens the other party's stance and unnecessarily drives up the cost of the process.

Frequently Asked Questions (FAQ)

Can my child refuse joint custody if they are over 12 years old?

The opinion of a minor aged 12 or older (or a younger child with sufficient maturity) is a very important element that the judge must obligatorily assess during the exploración del menor. However, the child's opinion is not binding on its own. The judge will analyse whether the minor's refusal is due to weighty reasons (such as a lack of relationship with the parent) or if they are being influenced by the other parent, always deciding what is considered most beneficial for their overall development.

If I switch to joint custody, will I automatically stop paying child support?

Not necessarily. There is a common misconception that joint custody eliminates child support (pensión de alimentos). If there is a notable economic disparity between the parents, the judge will order the parent with the higher income to pay an amount to ensure the minor enjoys similar living conditions in both households. If incomes are equivalent, the child support is usually eliminated, and common expenses are paid equally.

What happens to the use of the family home when changing to joint custody?

In sole custody arrangements, the use of the home is usually assigned to the minor and the custodial parent. Upon switching to joint custody, as there is no longer a single custodian, the general rule is that this exclusive assignment ceases. The judge may agree that the home be sold, that one parent keeps it while financially compensating the other, or assign its use temporarily and for a limited time (for example, for 1 or 2 years) to the parent in a worse economic situation so they can rebuild their life and find a new rental.

Is it mandatory to hire a lawyer and a procurador for this procedure?

Yes, in Spain, the intervention of a practicing abogado (lawyer) and a procurador (court representative) is mandatory both for filing a mutual agreement lawsuit for the modification of measures and for the contentious route. It is not possible to carry out this procedure privately before the court.

Can I request joint custody if my ex-partner moves to another autonomous community?

If the custodial parent decides to relocate unilaterally to a distance that makes joint custody or the relationship with the other parent unfeasible, the non-custodial parent can file an urgent lawsuit for the modification of measures. In these cases, the judge will evaluate whether the move is justified (for example, for imperative work reasons) and decide whether the minor should remain in their usual environment under the custody of the parent who stays, or if the move should be authorised, adapting the visitation regime accordingly.

In Summary

• Legal feasibility: Switching from sole to joint custody is perfectly possible in Spain through a modification of measures procedure (Article 90.3 of the Código Civil).
• The child's interest as a guide: Any change must be based on the child's benefit, not on the financial or personal interests of the parents.
• Procedural routes: Mutual agreement is the fastest (2 to 4 months) and cheapest route; the contentious route is longer (8 to 18 months) and requires a report from the Gabinete Psicosocial.
• Child support and housing: Joint custody does not automatically terminate child support if there is a financial imbalance, and it usually alters the right to use the family home.
• Mandatory representation: To initiate the process, it is strictly necessary to have representation by a procurador and defense by an abogado specialising in family law.

General legal information, not personalised legal advice. For your specific situation, ask your question for free at AbogadoAI — answers grounded in Spanish law (BOE), in English.

This is general information, not legal advice. Verify on the BOE or consult a lawyer for your specific case.