If you live with a partner in Sweden without being married, you are most likely a "sambo" (cohabitant) in the eyes of the law, even if you never registered or signed anything. Cohabitation here is governed by a specific statute, the Cohabitation Act (sambolagen, SFS 2003:376), and it sets out rules about how certain property is split if you separate or one of you dies. A cohabitation agreement (samboavtal) is the document that lets you change those default rules.
This matters because the default split is often a surprise to people who moved to Sweden from countries with different family-law traditions. By default the law treats only your shared home and household goods as joint property to be divided 50/50, regardless of who paid, while leaving most other assets untouched. A samboavtal lets you opt out of that division, in whole or in part, so the person who paid keeps what they paid for.
This guide explains, in plain English, what a samboavtal is, who counts as a sambo, what the law actually divides, the formal requirements for a valid agreement, and the common mistakes internationals make. It is general information based on official Swedish sources, not legal advice for your specific situation.
What is a samboavtal (cohabitation agreement)?
A samboavtal is a written contract between two cohabitants that overrides the default property-division rules in the Cohabitation Act (sambolagen). Under the Act, when a cohabitation relationship ends, either partner can request a division (bodelning) in which the "cohabitation property" (samboegendom) is split equally between them, no matter who bought it or paid for it. A samboavtal lets the couple agree that this division shall not take place at all, or that specific property shall be left out of it. In practice it is most often used so that the partner who bought the home or contributed more keeps their share instead of having to give away half. The agreement only concerns the property that the law would otherwise divide; it cannot bring in other assets, and it cannot decide inheritance. It is the cohabitation equivalent of a prenuptial agreement (äktenskapsförord) for married couples, but narrower in scope.
Who counts as a "sambo" under Swedish law?
The Cohabitation Act (§ 1) defines sambor as two people who live together permanently in a couple relationship and share a household. There is no registration, ceremony, or minimum time period written into the definition, and it applies regardless of the partners' genders. You can become a sambo, with all the legal consequences, simply by moving in together as a couple. Importantly, the Act does not apply if either of you is married to someone else, and a person can only be a sambo with one partner at a time. Because the status arises automatically from how you live, many internationals are sambos without realizing it, and are therefore already subject to the default division rules whether or not they have signed anything. Registering the same address with the Tax Agency (Skatteverket) is often taken as a strong indication of cohabitation, but the legal test is the real living arrangement, not the registration.
What the law actually divides (samboegendom)
This is the single most misunderstood point. The Cohabitation Act only divides "samboegendom," which is narrowly defined (§§ 3–7): the couple's shared home and household goods (bohag) that were acquired for joint use. The shared home can be a house, a tenant-owned apartment (bostadsrätt), or a rented flat, and household goods means furniture, appliances, and other movable items meant for the home. Crucially, it does not matter who paid; if the home was bought to live in together, it is normally split 50/50 on separation. What falls OUTSIDE samboegendom and is therefore NOT divided includes: bank accounts, savings, shares and other investments; cars, boats, and other vehicles; vacation/holiday homes (§ 7); anything either partner owned before moving in together; items used mainly by one person; and a home or goods acquired through gift, inheritance, or a will with a condition that it be the recipient's separate property (§ 4). So a partner's salary, savings, and a car they bought stay entirely theirs by default, with or without a samboavtal.
Legal requirements for a valid samboavtal
The formal requirements are short but strict (§ 9). The agreement must be in writing (skriftligen) and signed by both cohabitants (undertecknas av samborna). That is the core formality: an oral agreement or an informal understanding has no effect. Unlike a marital prenuptial agreement, a samboavtal does not need to be registered with any authority and does not need witnesses to be valid, though many people keep it with other important documents and store copies separately. You can sign it before you move in together, at the start of the relationship, or at any later point, and you can revoke or replace it later by a new written, signed agreement. One protective rule to be aware of: even a validly signed term can be adjusted or set aside in the division if a court finds it unreasonable (oskäligt) given its content, the circumstances when it was made, and later events (§ 9, third paragraph). So a wildly one-sided agreement is not automatically bulletproof.
When you actually need one (and the separation timeline)
You should seriously consider a samboavtal whenever the default 50/50 split of the home would not reflect what you both intend, for example when one partner buys the apartment with their own money or a gift from family, when the contributions to the home are very unequal, or when one partner brings a property into the relationship and the other later moves in. Without an agreement, the home bought for joint use is split equally even if only one name is on the contract. Note the timing rules if a relationship ends: a request for division (bodelning) must be made within one year of the cohabitation ending (§ 8); miss that deadline and the right to demand a division is generally lost. The relationship is considered ended if you separate, if you marry each other, or if one of you dies. There is also a rule (§ 17) that one partner may have the right to take over the shared home even against the other's wishes if they need it more, typically with compensation, which is another reason to settle expectations in writing in advance.
Common mistakes internationals make
The most frequent and costly mistake is assuming a samboavtal protects all your money. It does not; it only concerns the shared home and household goods. If you want to protect savings, investments, or keep finances fully separate in a binding way, a samboavtal is not the tool, and only marriage with a marital property agreement covers those assets. The second mistake is assuming a sambo automatically inherits the partner. They do not. Inheritance between cohabitants is governed by the Inheritance Code (Ärvdabalken), not by sambolagen, and without a will (testamente) the deceased's children, parents, or siblings inherit, never the surviving sambo. A samboavtal cannot create inheritance rights; only a will can. The law gives the survivor only a limited minimum protection, the "lilla basbeloppsregeln" (§ 18), which lets a surviving cohabitant who requests a division receive samboegendom up to two price base amounts, taken from the shared property only. Other mistakes include relying on an unsigned or oral agreement, not realizing you became a sambo just by moving in, and putting only one name on a jointly intended home and assuming that settles ownership, which it does not under the default division rule.
FAQ
Do I automatically become a sambo just by living with my partner?
Yes, in most cases. The Cohabitation Act applies to two people who live together permanently as a couple and share a household, with no registration or minimum time required, as long as neither is married to someone else. You can be subject to the default division rules without ever signing anything.
Does a samboavtal cover bank accounts, savings, and my car?
No. A samboavtal only concerns the shared home and household goods acquired for joint use, which is what the law would otherwise divide. Bank accounts, savings, investments, and cars are never part of cohabitation property (samboegendom) and stay with their owner by default. To regulate those assets bindingly you would need to marry and use a marital property agreement.
Does my sambo inherit from me if I die?
No. Cohabitants do not inherit each other under Swedish law. Inheritance is governed by the Inheritance Code (Ärvdabalken), so without a will your children, parents, or siblings inherit instead of your partner. A samboavtal cannot give inheritance rights; you need a will (testamente) for that. The survivor only has a small minimum protection of up to two price base amounts from the shared property (the lilla basbeloppsregeln).
What are the formal requirements for the agreement to be valid?
Under section 9 of the Cohabitation Act, the agreement must be in writing and signed by both cohabitants. It does not need to be registered with any authority or witnessed. However, a term can still be adjusted or disregarded in the division if a court finds it unreasonable.
What happens to the home if we separate and there is no samboavtal?
If the home was acquired for joint use, it is cohabitation property and is normally divided 50/50 on request, regardless of who paid for it or whose name is on the contract. Either partner can request the division, but the request must be made within one year of the relationship ending.
Can a samboavtal be set aside even if we both signed it?
Potentially, yes. Section 9 lets a court adjust or disregard a term that is unreasonable (oskäligt), judged by the content of the agreement, the circumstances when it was made, and later events. A heavily one-sided agreement is therefore not guaranteed to hold up in full.
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