Short answer. It depends on the cost. If the improvement's cost and any increase in value exceed the property's value at the time, the entire property becomes conjugal, subject to reimbursing you its earlier value. Otherwise you keep ownership, subject to reimbursing the partnership for the improvement's cost — with either outcome only finalized at liquidation.
What the law says
When the cost of the improvement made by the conjugal partnership and any resulting increase in value are more than the value of the property at the time of the improvement, the entire property of one of the spouses shall belong to the conjugal partnership, subject to reimbursement of the value of the property of the owner-spouse at the time of the improvement; otherwise, said property shall be retained in ownership by the owner-spouse, likewise subject to reimbursement of the cost of the improvement.
Family Code, Article 120 — Improvements on Exclusive Property (Reverse Accession). Read the full provision →
The default assumption before the comparison rule
Article 120 starts from the position that ownership of improvements made on a spouse's separate property, using conjugal money or through either spouse's efforts, can belong either to the conjugal partnership or to the original owner-spouse. Which one applies is not left to guesswork — the article sets a specific comparison to decide it, rather than defaulting automatically to either side.
The comparison that decides ownership
The test weighs the cost of the improvement plus any resulting increase in value against the value of the property at the time of the improvement. If the improvement and value increase are worth more than the original property was, the entire property shifts to the conjugal partnership. If not, the original owner-spouse keeps it, so the outcome turns on how the two figures compare.
Either outcome comes with a reimbursement obligation
Neither result lets one side simply absorb value for free. If the property becomes conjugal, the partnership must reimburse the owner-spouse for the property's value at the time of the improvement. If the owner-spouse keeps the property, they must instead reimburse the partnership for the cost of the improvement. Ownership does not shift outright without this offsetting payment being accounted for, whichever direction the comparison comes out.
When ownership actually vests
Article 120 is explicit that full ownership only vests upon the reimbursement, and that this reimbursement is made at the time of the liquidation of the conjugal partnership — not immediately when the improvement is built. Until liquidation actually happens and the reimbursement is settled, the question of ownership under this article remains provisional rather than final, even while the marriage and the partnership both continue as normal.
Cases citing this provision
These Supreme Court decisions cite the provision above. We list them so you can read them yourself; the summaries of what each decided are not ours to give.
- Josefa Bautista Ferrer vs. Sps. Manuel M. Ferrer & Virginia Ferrer, et al, G.R. No. 166496, November 29, 2006 — read the decision on LawPhil →
- Francisco Muñoz, Jr. vs. Erlinda Ramirez, et al, G.R. No. 156125, August 25, 2010 — read the decision on LawPhil →