What share of a separate-property home belongs to the community?
When one spouse owns a home before marriage and mortgage payments are made with marital earnings, the community earns an interest in the home. This calculator runs the standard Moore/Marsden formula and the main alternatives courts and experts use, including when the home was refinanced.
Dates
Home values
If the home was a self-supporting rental for part of the marriage, use the value on the date marital funds started paying the mortgage instead of the value at marriage.
Mortgage history
Start with the loan balance at purchase, then add the balance at marriage, at separation, and today. For a refinance, add two rows on the refinance date: the old balance being paid off, then the new loan balance with the box checked.
Results
Enter your dates, values, and mortgage history to see the results.
How each method works
Moore/Marsden always appears. The alternatives appear only when they fit your facts: Bono and Jafeman when the home was refinanced, and Branco when the refinance happened during the marriage.
Moore/Marsden. The community's share of appreciation during the marriage equals the principal it paid divided by the purchase price. The community also gets back the principal it paid.
Bono. Same idea, but the share is measured against the owner's equity at the date of marriage instead of the purchase price. Courts have used it when a premarital refinance makes the purchase price a poor measure.
Jafeman. Appreciation is split by each estate's share of all principal ever paid on the home.
Branco. When the home is refinanced during the marriage on community credit, the community can be treated as having paid off the separate loan balance at marriage, with the remaining community mortgage subtracted at the end.
Improvements. One approach adds marital spending on improvements back as a reimbursement. Another also treats that spending as a contribution and allocates appreciation on that basis.
This calculator is a general illustration. The right method depends on the facts, the documents available, and how a court or the parties choose to apply the law, and a premarital agreement can set its own rule. Talk with an attorney about how this applies to you.