Child Support in Spain: Splitting Expenses by Income

🇪🇸 Read the original in Spanish

When a relationship breaks down and there are children in common, one of the most recurring questions—and one that generates the most conflict in Spanish family courts—is how upbringing costs should be distributed. There is a false belief that children's expenses must always be split 50/50 between both parents. However, our country's legislation and case law establish a much fairer and more realistic criterion: proportionality based on the income of each parent. Understanding how this split works, which concepts are included in the maintenance allowance and what are considered extraordinary expenses is essential to guarantee the well-being of minors and avoid exhausting legal battles.

The Legal Framework: The Principle of Proportionality in the Civil Code

The Spanish legal system always places the best interests of the minor as the guiding principle of any family decision. Following a separation, divorce, or the breakdown of a pareja de hecho (de facto partnership), both parents maintain the obligation to provide maintenance to their children, a duty that stems from patria potestad (parental responsibility) itself.

The key to splitting these expenses is found in *Article 146 of the Código Civil (Civil Code)*, which strictly establishes:

> "The amount of maintenance (...) shall be adjusted to the proportion of the resources of the person giving it and the needs of the person receiving it."

Furthermore, *Article 145 of the Código Civil*** reinforces this idea by determining that, when the obligation to provide maintenance falls on two or more people, the payment will be split between them in an amount proportional to their respective wealth.

This rule of proportionality applies both to sole custody cases (where the non-custodial parent pays a monthly pensión de alimentos (child maintenance/allowance) to the custodial parent) and to joint custody arrangements. Contrary to popular belief, joint custody does not automatically exempt a parent from paying maintenance if there is a significant economic imbalance between the parents; the parent with the higher income must pay an amount to balance the minor's standard of living in both households.

For its part, Law 15/2005, of July 8, which amended the Código Civil regarding separation and divorce, promoted the streamlining of these processes and encouraged mutual agreement convenios reguladores (regulatory agreements), where parents can freely agree on this proportional split, subject to subsequent judicial approval to guarantee that the rights of the minors are covered.

It is worth noting that, in cases of special vulnerability, such as those covered by Organic Law 1/2004, of December 28, on Integrated Protection Measures against Gender Violence, the courts on violence against women have the jurisdiction to adopt urgent provisional measures regarding the use of the family home and the determination of child maintenance, prioritizing quick economic protection for minors.

Ordinary Expenses vs. Extraordinary Expenses: What is Each One?

To apply the proportionality of income correctly, we must first distinguish between the two main categories of expenses generated by children:

1. Ordinary expenses (Covered by the pensión de alimentos)

These are foreseeable, periodic, and necessary expenses for the sustenance, housing, clothing, medical assistance, and education of the child. Since they are habitual, they are calculated on an annual basis and prorated into 12 monthly payments (they are also paid in the summer, even if the child is on holiday with the non-custodial parent). They include:

• Food, hygiene, and footwear.
• Housing (proportional share of rent/mortgage and utilities such as electricity, water, and gas).
• Compulsory education: enrollment fees, monthly school fees (if it is a semi-private colegio concertado or a private school already attended during the marriage), school supplies at the start of the year, textbooks, AMPA (parent-teacher association) fees, and compulsory school trips.
• Transport and ordinary pocket money.

2. Extraordinary expenses

These are exceptional, unpredictable, non-periodic expenses that are necessary or, at least, highly convenient for the minor. These expenses are not included in the monthly pensión de alimentos and must be paid in the percentage determined in the court ruling or agreement (which, as we will see, does not have to be 50%). They are divided into:

• Necessary extraordinary expenses: Those indispensable for the health or education of the minor that are not covered by public healthcare or education (for example, orthodontic treatment, prescription glasses, orthopedic insoles, or private tutoring if the child is failing). They do not require the prior agreement of the other parent to be carried out, but they do require agreement for how they are split, although a judge will decide if there is a discrepancy.
• Non-necessary or superfluous extraordinary expenses: Those that are purely ornamental, leisure-related, or non-compulsory extracurricular activities (for example, tennis lessons, summer camps, end-of-year school trips, or First Communion celebrations). These strictly require the prior written consent of both parents before the expense is incurred. If one parent contracts them unilaterally without the other's consent, they will have to pay for them entirely out of their own pocket.

Practical Examples of Proportional Splitting

To understand how the theory of the Código Civil translates into real household economics, we will analyze two common scenarios using mathematical proportionality formulas.

Example 1: Joint custody with income disparity

Let's imagine Carlos and Sofía, who have joint custody of their 8-year-old child.

• Carlos earns a net monthly salary of €3,000.
• Sofía earns a net monthly salary of €1,500.
• The combined income of the theoretical family unit amounts to €4,500 per month.
• Carlos contributes 66.6% of the total income ($3,000 / 4,500 \times 100$), while Sofía contributes 33.3% ($1,500 / 4,500 \times 100$).

If the minor's fixed monthly expenses (school, canteen, already established activities, private medical insurance) total €600 per month, the split will not be half (€300 each). The rule of proportionality will apply:

• Carlos will pay 66.6% of those expenses: €400 per month.
• Sofía will pay 33.3% of those expenses: €200 per month.

In addition, for any extraordinary expenses that may arise (such as an orthodontic treatment costing €2,400), the same proportion will apply: Carlos will take on €1,600 and Sofía will take on €800.

Example 2: Sole custody with rented housing

Let's assume the case of María and Juan. María has sole custody of their 12-year-old daughter, and Juan has a visitation schedule of alternate weekends and two weekday afternoons.

• Juan has a net income of €2,500 per month.
• María has a net income of €1,200 per month.
• María rents a flat to live in with her daughter for €900 per month.

In this case, to set the pensión de alimentos that Juan must pay, the judge will look not only at the minor's direct expenses (food, clothes) but also at the indirect expenses indispensable for her housing. The rent cost of €900 is partially attributed to the minor (it is usually calculated that a minor generates 30% or 50% of the housing cost; in this case, let's estimate 30%, equivalent to €270).

Adding the minor's direct expenses (€350) and her share of housing (€270), the daughter's total maintenance cost is €620 per month. Given that Juan earns 67.5% of both parents' total income, the judge will set a pensión de alimentos to be paid by Juan of approximately €420 per month, with the rest covered by María's in-kind and financial contribution.

Step-by-Step Practical Steps to Set or Modify the Split

If you are in the process of separating or need to readjust financial contributions because the financial situation of one of the parents has changed, you must follow these steps:

1. Gathering documentary evidence: Collect the last 3 payslips, the IRPF (personal income tax) return for the last financial year, employment contracts, bank statements, and historical receipts of children's expenses (school enrollment, activity receipts, medical bills, etc.).
2. Drafting a budget proposal: Prepare a detailed table that clearly distinguishes between monthly ordinary expenses and the forecast of annual extraordinary expenses.
3. Out-of-court negotiation (Mutual agreement route): This is the fastest, cheapest, and least emotionally damaging route. Through your respective lawyers, a Convenio Regulador is drafted, detailing the splitting percentages for ordinary and extraordinary expenses based on your current incomes. This agreement is presented to the Juzgado de Primera Instancia (Court of First Instance) for ratification and subsequent judicial approval.
4. Filing a lawsuit (Contested route): If an agreement is impossible, a lawsuit for divorce or parental measures must be filed. In court, each party will present their financial capacity, and the judge, based on the evidence presented and the Tablas Orientadoras (guideline tables) of the Consejo General del Poder Judicial (CGPJ - General Council of the Judiciary), will issue a ruling setting the exact amounts and splitting percentages.
5. Filing for a Modification of Measures (If a ruling already exists): If either parent's income changes substantially over time (for example, due to long-term unemployment, a major promotion, or the emergence of new needs for the minor), a demanda de modificación de medidas (lawsuit for modification of measures) must be filed. It is vital to remember that maintenance payments cannot be modified unilaterally; until a judge issues a new ruling, the previous one remains fully in force and is legally binding.

Deadlines, Amounts, and Key Figures You Must Know

• 12 monthly payments: The pensión de alimentos must be paid during the 12 months of the year, with no exceptions for holiday periods when the minor is with the paying parent.
• Annual update according to the IPC: The amount of the pensión de alimentos must be updated every year. The deadline to do so is usually January 1st of each year or on the anniversary date of the court ruling, applying the IPC (Consumer Price Index) published by the Instituto Nacional de Estadística (INE - National Statistics Institute).
• Mínimo vital (Minimum subsistence level): Spanish courts establish a mínimo vital that ranges between €150 and €200 per month per child. This amount is imposed on the parent obligated to pay even in situations of extreme financial hardship or unemployment, except in cases of proven absolute destitution.
• 5-year statute of limitations: If the parent obligated to pay does not pay the maintenance or their share of extraordinary expenses, the creditor parent has a period of 5 years to legally claim the back payments, according to *Article 1966 of the Código Civil***. After this period, the debt from previous months expires and cannot be demanded.
• Criminal consequences: Failure to pay the pensión de alimentos for 2 consecutive months or 4 non-consecutive months is classified as a crime of family abandonment under *Article 227 of the Código Penal (Criminal Code), with penalties ranging from financial fines to prison sentences of 3 months to 1 year*.

Mistakes You Must Avoid

• Agreeing to a 50/50 split by default if there is a large income inequality: Agreeing to an equal split when one parent earns three times more than the other will financially suffocate the parent with fewer resources and directly harm the minor's quality of life when under their care.
• Leaving agreements as verbal promises without judicial validity: Verbal agreements or private documents signed "at the kitchen table" are not judicially enforceable. If one parent stops paying, you will not be able to freeze their accounts or demand payment through enforcement proceedings unless you have an agreement approved by a judge.
• Unilaterally stopping maintenance payments due to unemployment: If you lose your job or your income drops drastically, never stop paying maintenance on your own. You must continue paying it and immediately file a lawsuit for modification of measures so that the judge can legally reduce the amount.
• Incurring non-necessary extraordinary expenses without written consent: Enrolling the minor in an expensive extracurricular activity or a private school without having the express, written "yes" (a clear email or WhatsApp message is sufficient) of the other parent will prevent you from legally claiming their share of the payment.

Frequently Asked Questions (FAQ)

What happens if my ex-partner refuses to pay their percentage of a necessary medical extraordinary expense?

If the expense is necessary (such as orthopedic insoles or orthodontic treatment prescribed by a doctor) and your ex-partner refuses to pay for it or give their consent, you must initiate the procedure under *Article 156 of the Código Civil*** to request judicial authorization. Once the judge declares that the expense is necessary and must be paid jointly, if they still do not pay, you can file a lawsuit for enforcement of the ruling to garnish the corresponding amount directly from their bank accounts or payslip.

Do extraordinary expenses and the pensión de alimentos terminate automatically when the child turns 18?

No. In Spanish family law, reaching the age of majority does not terminate the obligation to provide maintenance. This obligation is maintained as long as the child continues their studies diligently and does not have financial independence due to reasons not attributable to them. To terminate the maintenance of an adult child who is no longer studying or working, the paying parent must file a judicial lawsuit for the termination of maintenance; payment must never be withdrawn unilaterally.

In joint custody, if we earn the same, is it mandatory to open a joint account?

It is not mandatory by law, but it is the most recommended practical tool by the courts. What is common in joint custody arrangements with identical incomes is to open a joint bank account where each parent deposits the same agreed amount monthly (for example, €250 each) and from which all school, medical, and leisure bills for the minor are direct-debited.

How does it affect things if one parent cohabits with a new partner in the family home?

The cohabitation of a new romantic partner in the family home that has a ganancial (community property) character can be grounds to request a review of the measures. The Tribunal Supremo (Supreme Court) has established that the entry of a third party into the family home changes its character, as it ceases to serve exclusively the purposes of the dissolved marriage, which can influence the reduction of indirect child maintenance (housing) or the liquidation of the use of said property.

Summary

• Legal proportionality: The split of children's expenses does not have to be 50/50; the law requires it to be adjusted to the real income of each parent.
• Ordinary vs. Extraordinary expenses: Ordinary expenses are covered by the monthly maintenance allowance, while extraordinary expenses are paid separately according to the judicially fixed percentage.
• Written consent: Non-necessary extraordinary expenses always require the prior written agreement of both parents to demand shared payment.
• Compulsory update: The pensión de alimentos must be updated annually in line with the IPC to prevent it from losing purchasing power.
• Judicial route for changes: Any reduction or increase in amounts due to changes in income must be processed through a lawsuit for modification of measures.

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.