Anyone who discovers that their partner is having an affair will, at least from a legal standpoint, ask themselves: Does this automatically put me at an advantage? Austrian law offers a straightforward answer: not necessarily. Whether infidelity actually plays a decisive role in divorce proceedings depends on circumstances that very few people are aware of.
Adultery as a serious breach of marital fidelity—but not an automatic consequence
Section 49 of the Austrian Marriage Act (EheG) explicitly cites adultery as an example of a serious breach of marital fidelity. That sounds clear. However, it is not entirely accurate. Since the reform of the Marriage Act in 1999, there are no longer any absolute grounds for divorce. Adultery leads to a fault-based divorce only if it was the cause of the irretrievable breakdown of the marriage. The court therefore examines not only whether someone was unfaithful, but also whether this behavior actually destroyed the marriage.
If the marriage was already irretrievably broken at the time of the affair, adultery can no longer be considered a cause of the breakdown of the marriage. It thus loses its legal weight—at least as a primary ground for divorce.
What the Supreme Court clarified in 2024
In its decision 5 Ob 51/24x of July 4, 2024, the Supreme Court ruled on a situation that occurs more frequently in practice than one might think: A husband begins extramarital affairs shortly after the wedding. The wife finds out about this. She initially takes no action, but later commits marital infidelity herself.
In this decision, the Supreme Court reiterated that while adultery is one of the most serious breaches of marital fidelity, it must have a disruptive effect in order to qualify as grounds for divorce. The decisive factor is therefore how the betrayed spouse reacted to the infidelity. If he or she continued the marriage in full knowledge of the affair without initiating divorce proceedings, the court may infer implied forgiveness within the meaning of § 56 of the Marriage Act. A marital offense that has been forgiven can no longer be asserted as grounds for divorce.
In plain language, this means that anyone who waits months or years after discovering the infidelity risks losing their legal advantage. The six-month period specified in § 57 of the Marriage Act, starting from the date of certain knowledge, is only one aspect of this. Simply continuing to live together can have even more serious consequences.
The European Dimension: ECtHR, H.W. v. France
Almost simultaneously with this development in Austrian case law, the European Court of Human Rights issued a decision on January 23, 2025, that has attracted widespread attention. In the case of H.W. v. France (Application No. 13805/21), the ECtHR ruled on a case in which a woman had been granted a divorce on the grounds that she was solely at fault—not because of an affair, but because she had persistently refused to engage in marital relations.
French law provides for divorce on the grounds of fault in cases of serious and repeated breaches of marital obligations. The courts had ruled that this constituted grounds for fault. The ECtHR saw it differently. It found a violation of Art. 8 of the ECHR—the right to respect for private life. The Court held that the concept of marital duties without any reference to consent violates sexual freedom and bodily autonomy. Marriage is not a blank check for all future sexual acts.
This decision does not apply directly to Austria. While Austrian law also recognizes the persistent and unjustified refusal to have sexual intercourse as a possible breach of marital obligations under § 49 of the Marriage Act (EheG), the ECtHR’s decision makes clear the direction in which the European understanding of human rights is evolving: sexual autonomy is a fundamental right protected by Article 8 of the European Convention on Human Rights (ECHR), which also applies within marriage. National courts will increasingly have to take this assessment into account when interpreting § 49 of the Marriage Act.
This is a development that goes far beyond this specific French case. It fundamentally raises the question of where the line is drawn between the marital duty of fidelity and personal autonomy.
What does this mean for those affected?
Anyone who discovers that their partner has been unfaithful should act quickly and methodically. The six-month period under § 57 of the Marriage Act begins when the infidelity is confirmed—not when it is first suspected. Waiting is risky. Anyone who continues the marriage while aware of the infidelity risks implying forgiveness.
Equally important is the question of evidence. Adultery must be proven. Evidence may include chat messages, witness statements, or reports from a private investigator. The Supreme Court has repeatedly confirmed that properly obtained investigator’s reports are admissible as evidence and that the costs incurred are recoverable as litigation costs under certain conditions.
If you have concrete evidence of marital infidelity or are facing such allegations yourself, seeking legal advice early on is crucial. The legal situation can change dramatically within a matter of weeks.
As divorce attorneys in Vienna, we are happy to assist you with an initial assessment of your situation.
