You may need a consultation if
- You held a wedding but kept putting off registering the marriage
- You have lived together for years and were introduced to both families as a married couple
- Your de facto spouse started seeing someone else and moved out
- The affair partner says, "I thought they were just living together"
- Your partner turned out to have a legally registered spouse
Relevant provisions
Civil Act (민법) Articles 750 and 751 (Tort; non-property damage)
A person who unlawfully causes damage, intentionally or negligently, must compensate for it, and emotional suffering is also compensable. Compensation claims against a de facto spouse and an affair partner also start from these provisions.
Civil Act Article 766 (Extinctive prescription of damage claims)
The claim lapses 3 years after the day the victim learned of the damage and the wrongdoer, or 10 years after the day of the unlawful act.
Statutes are summarized. The official Korean text is available at the Korea Law Information Center (law.go.kr).
First show that it was a de facto marriage
A de facto marriage (사실혼) is a relationship in which two people, intending to marry, actually lived together as a married couple. It is not decided by the length of cohabitation alone; the court looks at whether people around you treated you as spouses and whether you ran your lives together.
If it is judged to be cohabitation while dating, it is difficult to claim compensation (위자료) from either your partner or the affair partner. So in de facto marriage cases, evidence showing the substance of the relationship matters as much as evidence of infidelity (부정행위).
- Wedding photos, wedding invitations, records of the families' formal first meeting
- Records of attending both families' holidays, weddings and funerals together
- Bank records of sharing living expenses or loans
- Hospital or school documents listing your partner as spouse or guardian
- Records of moving in at the same address, lease agreements
The affair partner must have known about the de facto marriage
Because the marriage was not registered, affair partners often argue, "I didn't know they were a married couple." You need evidence that the affair partner knew the two of you lived together, or that you had held a wedding.
Useful evidence includes chats in which your partner referred to you as "my wife" or "my husband" to the affair partner, records of meeting near your shared home, and wedding photos posted on social media.
Some de facto marriages are not protected
A de facto marriage with someone who has a separate legal spouse does not, absent special circumstances, receive protection comparable to a legal marriage. Case law holds the same even when the legal spouse had left home long ago (Supreme Court Decision 96므530, rendered September 20, 1996).
Conversely, if you are the legal spouse and your spouse is living with someone else as if in a de facto marriage, that person can be held liable as the affair partner.
Ending the relationship and compensation are considered together
A de facto marriage can be ended without any filing, so when an affair comes out, ending the relationship, compensation and property issues are often disputed all at once. You need to decide whether to proceed against your de facto spouse only, the affair partner only, or both.
A compensation claim must be made within 3 years of the day you learned of the damage and the wrongdoer. Keep a record of the date the relationship ended and the date you learned of the affair.
How Jisan Law's Family Law Center handles your case
- 1
Assessing the relationship
We hear when you began living together, about the wedding and how living expenses were managed, and first judge whether a de facto marriage is likely to be recognized.
- 2
Sorting the evidence
We organize evidence showing the substance of the relationship separately from evidence of infidelity.
- 3
Choosing whom to sue
We decide whether to proceed against the de facto spouse, the affair partner or both, and whether to dispute property issues at the same time.
- 4
Lawsuit and mediation
If the other side denies the de facto marriage, we rebut with witnesses and documents; in mediation, we negotiate compensation and the division of property together.
Lawyers handling these cases
Hansol Kim Managing Partner
Former prosecutor at the Incheon District Prosecutors' Office, the Ansan Branch of the Suwon District Prosecutors' Office and the Hongseong Branch of the Daejeon District Prosecutors' Office
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Miso Kim Partner
Formerly at Daehwan Law Firm, in-house counsel on the legal team of Wemade Co., Ltd., and Oracle Law Firm
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Frequently asked questions
We lived together for 2 years without registering the marriage. Is that a de facto marriage?
It is not decided by length alone. The court looks together at whether there was an intention to marry, whether both families and people around you knew you as a married couple, and whether you ran your lives together. If it looks like cohabitation while dating, it is hard to get the protection given to de facto marriages.
We lived apart because of our jobs. Can it still be a de facto marriage?
Even if you lived apart because of your respective jobs, a de facto marriage can be recognized if you held a wedding, attended family events together and lived as a married couple. Prepare material showing why you lived apart and how often you visited each other.
Can I claim against the affair partner only?
Yes. However, even in a lawsuit against the affair partner alone, you must still prove that it was a de facto marriage and that the affair partner knew about that relationship.