Prenups and the Home

What a Premarital Agreement Can Say About Property

A premarital agreement, usually called a prenup, is a written contract between two people who plan to marry, setting out how money and property will be handled. Family Code section 1610(a) defines it as "an agreement between prospective spouses made in contemplation of marriage and to be effective upon marriage." Under Family Code section 1613, it takes effect on the wedding day, not on the day it is signed. Section 1611 requires it to be in writing and signed by both parties.

The legal starting point is Family Code section 1500, which says the property rights of spouses set by statute "may be altered by a premarital agreement or other marital property agreement." In other words, California has default rules, and a prenup lets the couple write different ones.

Family Code section 1612 lists what the agreement may cover. Several items bear directly on a home:

• Section 1612(a)(1): "The rights and obligations of each of the parties in any of the property of either or both of them whenever and wherever acquired or located."
• Section 1612(a)(2): the right to buy, sell, use, transfer, lease, mortgage, encumber, or "otherwise manage and control property."
• Section 1612(a)(3): "The disposition of property upon separation, marital dissolution, death, or the occurrence or nonoccurrence of any other event."
• Section 1612(a)(4): "The making of a will, trust, or other arrangement to carry out the provisions of the agreement."

The phrase "whenever and wherever acquired" matters a great deal for real estate. It means a prenup is not limited to a house someone already owns. It can address a home bought five years into the marriage, a vacation property outside California, or a house that has not been picked out yet. Section 1610(b) defines "property" broadly, including present and future interests in real property.

There are outer limits. Section 1612(b) says a prenup cannot adversely affect a child's right to support, and section 1612(a)(7) allows other matters only if they do not violate public policy or a statute imposing a criminal penalty.

California's Default Rules: Community Property and Separate Property

Without an agreement, California sorts a married couple's property into two categories. Community property is, generally, property either spouse acquires during the marriage; it belongs to both spouses equally, no matter whose paycheck paid for it or whose name is on the title. Separate property is, generally, property a spouse owned before the marriage, or received during the marriage as a gift or inheritance; it stays that spouse's own.

For a home, the practical result usually looks like this. A house one partner bought before the wedding is generally that partner's separate property. A house bought during the marriage with earnings from the marriage is generally community property. Real life tends to blur those lines. Marital income pays a premarital mortgage, or separate savings fund a marital down payment, and the house ends up with mixed character.

A prenup lets the couple choose rules other than these defaults. Without one, the Family Code defaults govern, and any disagreement about how to classify the home is decided by a judge.

In San Diego County, that judge sits in the Superior Court of California, County of San Diego. The court has four family law divisions: Central, North County, East County, and South County. Which one hears a case depends on ZIP code, under the court's ZIP Code List (ADM-254).

How a Prenup Addresses a Home Owned Before Marriage

A house owned before the wedding starts out as separate property under California's default rules. So it is fair to ask why a prenup needs to mention it at all. The answer is that the house's character can shift over the years in ways most couples do not notice while it is happening.

The most common way is the mortgage. When earnings from the marriage, which are community property, go toward paying down the loan principal on one spouse's premarital home, California courts can recognize a community property interest in that home. Courts call this Moore/Marsden apportionment: the community gains a share tied to the principal it paid down, and the house's value is divided between the separate and community shares. It does not matter that only one spouse is on the deed. For someone who bought a home on their own and has been paying for it for years, discovering that marriage can quietly create a shared interest is often the point at which the prenup question becomes real.

A prenup can speak to this directly. It can state that the home remains the owning spouse's separate property. It can say whether mortgage payments made during the marriage, even from marital income, create a community interest, or instead are treated as the owning spouse's separate obligation. It can also address improvements, rental income, and what happens to the house if a spouse dies. Clear terms on these points make the home's character harder to dispute later, though no agreement assures a particular result if it is challenged.

One related rule is easily confused with Moore/Marsden, and it runs in the opposite direction. Family Code section 2640 gives a spouse a right to reimbursement when that spouse's separate property money goes into community property, for example a down payment on a home the couple owns as community property. Section 2640(c) also generally reimburses a spouse's separate property contributions to the other spouse's separate property. Moore/Marsden concerns community money flowing into one spouse's separate-property home; section 2640 concerns separate money flowing into community property or into the other spouse's separate property. They are different rules with different results.

How a Prenup Addresses a Home Purchased During Marriage

Planning ahead for a house that hasn't been bought yet raises a different set of questions. By default, a home bought during the marriage with community funds is generally community property, which means it belongs equally to both spouses.

Because section 1612(a)(1) reaches property "whenever and wherever acquired," a prenup can set different terms for a future home. It might say that a house bought in one spouse's name will be that spouse's separate property. It might go the other way and say that a jointly purchased home will be community property, even though one spouse supplies the down payment from separate savings.

Mixed funding is where these terms tend to matter most. Suppose one spouse brings a large separate-property down payment and the other contributes little or nothing toward it. Without an agreement, the contributing spouse may be able to claim reimbursement under section 2640(b), traced to a separate property source. That reimbursement is "without interest or adjustment for change in monetary values" and cannot exceed the net value of the property at the time of division. Section 2640(b) also recognizes that a party can make "a written waiver of the right to reimbursement." A prenup can be that writing, or it can preserve the right, or it can set up a different split entirely, such as ownership shares tied to each spouse's contribution.

When no agreement addresses these points, the spouses are left with section 2640 reimbursement or Moore/Marsden apportionment at the end of the marriage, and both can be contested. The agreement's value lies in its specificity. Language that names the property or the class of property covered, such as "any residence acquired during the marriage," and explains how down payments, loan payments, and title will be treated, gives a court much less to argue about than a general statement that "each party keeps what is theirs."

Transmutation: Changing a Home's Character During Marriage

Transmutation is the legal term for changing the character of property: separate to community, community to separate, or one spouse's separate property to the other spouse's. For a home, the most familiar example is adding a spouse's name to the deed.

California sets a firm rule for how a transmutation happens. Family Code section 852(a) states:

"A transmutation of real or personal property is not valid unless made in writing by an express declaration that is made, joined in, consented to, or accepted by the spouse whose interest in the property is adversely affected."

Section 852(b) adds a second requirement specific to real estate:

"A transmutation of real property is not effective as to third parties without notice thereof unless recorded."

The practical meaning is that changing who owns a home during marriage takes more than a conversation or an assumption. A deed change can be a transmutation, and to be valid between the spouses it has to meet section 852(a)'s requirement of a written, express declaration by the spouse who is giving something up. Recording under section 852(b) is what makes the change effective against outside parties, such as buyers or lenders, who lack notice of it. Section 852(d) notes that the statute does not change the separate law governing commingled property.

A prenup can look ahead to these situations. Because section 1612(a)(7) lets the parties address other matters not against public policy, an agreement can state the couple's intent about what certain future acts mean, for instance that refinancing in both names or adding a spouse to title for lending purposes is not meant to change the home's character. That does not take transmutation off the table. Spouses remain free to change a home's character later by meeting section 852's requirements, and after the wedding, section 1614 allows the prenup itself to be amended or revoked only by a written agreement signed by both. Any terms the prenup sets about the home are also only as strong as the prenup itself, which brings in section 1615.

What Makes a Prenup Enforceable in California

Careful house provisions do little good if the agreement as a whole falls apart. Family Code section 1615 sets the rules for when a prenup can be enforced against the spouse who later challenges it.

Under section 1615(a), the agreement is not enforceable if that spouse proves either that the agreement was not signed voluntarily, or that it was unconscionable, meaning grossly unfair, when signed and, before signing, all three of these applied: the spouse did not receive a fair, reasonable, and full disclosure of the other party's property or financial obligations; did not voluntarily and expressly waive further disclosure in writing; and did not have, or reasonably could not have had, adequate knowledge of the other party's property or financial obligations. Section 1615(b) leaves unconscionability for the court to decide as a matter of law.

Section 1615(c) makes "voluntary" a demanding standard. The court treats the agreement as not voluntarily signed unless it finds, in writing or on the record, all of the following:

• Independent counsel. The challenging spouse was represented by independent legal counsel when signing, or, after being advised to seek counsel, expressly waived representation in a separate writing. The advisement has to come at least seven calendar days before the final agreement is signed.
• The seven-day rule. For agreements signed on or after January 1, 2020, the spouse had at least seven calendar days between first receiving the final agreement and signing it, whether or not represented. Agreements signed between January 1, 2002, and January 1, 2020, have a related seven-day rule tied to the advisement to seek counsel. Nonsubstantive amendments that do not change the terms are excepted.
• Explanation for an unrepresented party. A spouse without a lawyer must have been fully informed, in writing, of the agreement's terms and basic effect and the rights being given up, in a language the spouse is proficient in, and must sign a document confirming receipt and naming who provided the information.
• No duress, fraud, or undue influence, and no lack of capacity.
• Any other factors the court finds relevant.

Spousal support terms carry their own rule. Under section 1612(c), a provision about spousal support, including a waiver, is not enforceable if the spouse against whom it is enforced lacked independent counsel when signing, or if the provision is unconscionable at the time of enforcement. Whether any particular agreement holds up depends on how it was made and on the facts a court finds.

What Happens Without a Prenup

When a marriage ends in California without an agreement, the default rules take over. Family Code section 2550 directs the court to divide the community estate equally, unless the parties agree otherwise in writing or by oral stipulation in open court. Separate property is not part of that division.

The hard part is usually deciding what is community and what is separate. For a home, that tends to mean tracing: following the money used to buy, pay down, or improve the property through bank records, escrow and loan documents, and years of financial history. A premarital house with a mortgage paid partly from marital earnings, or a marital house bought with a separate down payment, can turn into one of the more involved issues in a California divorce.

Timing of value is often misunderstood. Under Family Code section 2552, the court values community assets and liabilities as near as practicable to the time of trial. On 30 days' notice and for good cause, it may use a date after separation and before trial. For a home whose value moves over a long case, that rule can matter.

A prenup is not the only document that can address a home. Married couples can sign a postnuptial agreement during the marriage, and it can cover some of the same ground. Because spouses already owe each other a fiduciary duty of "the highest good faith and fair dealing" under Family Code section 721, an agreement made during marriage is reviewed under different standards than a prenup.