Null and Void Dismissal in Spain: Risks for Employers

Null and void dismissal in Spain is declared when a company’s decision breaches fundamental rights, public freedoms, or is based on a specially protected ground of discrimination.

Unlike an unfair dismissal, the employer has no right to choose between reinstatement and compensation: reinstatement of the worker is mandatory, back pay must be covered, and, almost systematically today, an additional award for moral damages is granted.

In recent years, the courts have tightened their scrutiny of dismissals linked to specially protected situations: illness, discrimination, pregnancy, maternity/paternity, or retaliation for previously exercising employment rights. The key for employers is not that dismissal becomes impossible in these contexts, but that the decision must respond to a genuine, objective, proportionate and rigorously evidenced cause.

What is a null and void dismissal in Spain?

A null and void dismissal is one carried out in breach of a worker’s fundamental rights and public freedoms, or where the employer’s decision is motivated by one of the grounds of discrimination prohibited by the Constitution or by law.

Article 55.5 of the Workers’ Statute (note: the text of Royal Legislative Decree 1/1995 has since been repealed, although the grounds for objective nullity relating to maternity, paternity, breastfeeding and family responsibilities remain fully in force under current legislation and are consistently applied by case law) sets out the circumstances in which a dismissal must be declared null and void, including:

• Dismissals motivated by any of the grounds of discrimination prohibited by the Constitution or by law.
• Dismissals carried out in breach of the worker’s fundamental rights and public freedoms.
• Dismissals during periods of contract suspension due to birth, adoption, foster care for adoption purposes, guardianship, risk during pregnancy, or risk during breastfeeding.
• Dismissals of pregnant workers, from the start of the pregnancy until the beginning of the suspension periods mentioned above.
• Dismissals of workers who have requested or are enjoying reduced or adapted working hours to care for family members.

Law 15/2022 of 12 July on equal treatment and non-discrimination has substantially strengthened protection against employer decisions linked to illness, state of health, ongoing medical treatment, or genetic predisposition to disease.

This does not mean that every dismissal occurring during a protected situation is automatically null and void. Nullity requires a causal link between the protected circumstance and the employer’s decision, or that the employer is unable to prove a cause unrelated to that circumstance capable of rebutting the presumption of discrimination.

How does a null and void dismissal differ from an unfair dismissal?

One of the issues that most often confuses HR practice is the difference between an unfair dismissal and a null and void one:

• Unfair dismissal. Declared when the employer fails to prove the truth of the ground alleged in the dismissal letter, or fails to meet the legally required formalities. Under Article 56 of the Workers’ Statute, the employer has the right to choose (unless the worker is an employee representative) between reinstatement and payment of the statutory severance. You can read more on this in our article on disciplinary dismissal in Spain.
• Null and void dismissal. Directly affects fundamental rights or cases of objective legal protection. The employer has no right to choose: reinstatement is mandatory, back pay must be covered, and it opens the door to a claim for moral damages.

For this reason, correctly identifying the risks and the worker’s personal context before taking a termination decision is essential to the organisation’s economic viability.

Illness and sick leave: one of the main risks of null and void dismissal in Spain

Illness and state of health have become one of the most litigated areas in Spanish employment courts. Following the entry into force of Law 15/2022 of 12 July, illness became expressly recognised as a protected ground against discrimination under its Article 2.1.

This does not amount to an absolute “shield” preventing the dismissal of a worker on temporary incapacity (sick leave). The key lies in proving that the decision responds to genuine, serious, objective reasons entirely unrelated to the worker’s health.

Where there is close temporal proximity between the sick leave and the dismissal, the courts consider this to generate a well-founded indication of discrimination. In that scenario, the burden of proof shifts, requiring the employer to provide an objective, reasonable and sufficiently evidenced justification for the termination, as analysed in the High Court of Justice ruling.

How is the burden of proof distributed in a possible null and void dismissal?

One of the most relevant elements in null and void dismissal proceedings is how the burden of proof is allocated. Under Article 96.1 of Law 36/2011 of 10 October, governing employment tribunal proceedings:

“In proceedings where the claimant’s allegations give rise to a well-founded indication of discrimination on grounds of sex, sexual orientation or identity, racial or ethnic origin, religion or belief, disability, age, harassment, or any other breach of a fundamental right or public freedom, it falls to the defendant to provide an objective and reasonable, sufficiently evidenced, justification for the measures adopted and their proportionality.”

The worker does not need to fully prove the existence of discrimination; it is enough to provide an indication or prima facie case suggesting the breach may have occurred, as established in Supreme Court case law (Roj: STS 1789:2025 · ECLI: ES:TS:2025:1789). Once that indication has been provided, the burden of proof shifts entirely to the employer, who must prove that the measure adopted is proportionate and responds to genuine causes unrelated to any discriminatory purpose.

Which specially protected situations increase the risk of nullity?

Certain scenarios significantly increase the risk of nullity, due to the objective protection afforded by law:

• Pregnancy, birth and family responsibilities. Nullity applies objectively: the dismissal is automatically declared null and void unless the employer proves a cause serious enough to justify the measure, regardless of whether the employer was aware of the worker’s pregnancy.
• Guarantee of indemnity (exercise of employment rights). Protects workers against employer retaliation for bringing legal claims, internal complaints, reports to the Labour Inspectorate, or trade union activity. If the dismissal is a reaction to a prior claim, it is declared null and void for breaching the right to effective judicial protection (Article 24 of the Spanish Constitution), as reflected in the High Court of Justice ruling (Roj: STSJ EXT 1269:2025 · ECLI: ES:TSJEXT:2025:1269).
• Discrimination on personal or social grounds. Dismissals motivated by gender, age, disability, sexual orientation, origin, religion or state of health. See also our content on workplace discrimination and harassment.

What documentation protects an employer against a declaration of nullity?

The most decisive factor in defending a dismissal against a potential finding of nullity is having built the documentary evidence in advance. The employer must be able to show the decision is based on objective circumstances and not on a prohibited ground. To that end, it is essential to keep and produce:

• Regular, objective performance evaluations.
• Internal communications and written warnings.
• Technical or organisational reports justifying the elimination of the position.
• Up-to-date sales, production or accounting data.
• Prior internal investigations that reconstruct the facts impartially (see our guide on internal workplace investigations).

A generic dismissal letter lacking factual detail will be indefensible in court if the worker is in a specially protected situation, since it will prevent the employer from proving a genuine cause unrelated to discrimination.

What are the consequences of a dismissal declared null and void?

A judicial declaration of nullity carries particularly serious consequences:

• Mandatory reinstatement. The employer must immediately reinstate the worker to the same position and under the same conditions that applied before the dismissal.
• Payment of back pay. Payment of all wages not received from the date of dismissal until notification of the nullity judgment.
• Compensation for moral damages. Under Article 183 of Law 36/2011 of 10 October, governing employment tribunal proceedings, the judge must rule on the amount of compensation for moral damage arising from the breach of fundamental rights, to be set prudently by the court where it is difficult for the claimant to provide a detailed basis for calculation, as established by the Supreme Court (Roj: STS 5931:2025 · ECLI: ES:TS:2025:5931).

What role should HR play in a potential null and void dismissal?

HR departments play a strategic role in preventing nullity risks. Before communicating any dismissal, HR should carry out a thorough preventive review:

1. Check whether the worker is in any situation of objective protection (reduced working hours, breastfeeding, etc.).
2. Assess whether there is temporal proximity to sick leave or to prior complaints (guarantee of indemnity).
3. Evaluate whether the ground alleged in the dismissal letter is backed by solid, sufficient documentary evidence.
4. Coordinate with management and external legal advisers to assess the level of risk involved.

Best practices to reduce the risk of null and void dismissal

• Document on an ongoing basis. Don’t wait for a dispute to start generating evidence: performance evaluations, written warnings and activity records should be part of routine management.
• Avoid acting hastily. Don’t dismiss immediately after sick leave or an internal complaint; allow a reasonable period to pass and build solid evidence of the genuine cause for dismissal.
• Apply consistent criteria. Sanction or terminate contracts using the same objective benchmarks across the workforce, to avoid any suspicion of discriminatory treatment.
• Seek specialised legal advice. Analyse complex cases in advance to design an exit strategy that minimises litigation exposure.

Core legal takeaway

Null and void dismissal represents one of the main legal risks in employment management in Spain. Not because it limits an employer’s ability to make organisational or disciplinary decisions, but because it requires those decisions to be properly grounded, documented, and entirely free of any discriminatory motive.

The courts do not only examine the outcome of the employer’s decision, but also the context in which it was made and the employer’s ability to prove a legitimate cause existed. Proper preparation beforehand, solid documentation and an appropriate risk assessment can significantly reduce litigation exposure.

At Suárez de Vivero we advise national and international companies on dismissals, employment litigation, fundamental rights, discrimination, internal investigations and court defence before the employment tribunals.

Frequently asked questions about null and void dismissal in Spain