Executive summary

When a person dies, ownership and possession of their property pass to the heirs at the moment of death. A live-in partner (i.e., an unmarried cohabitant) is not an heir and does not inherit — but they may (1) be a co-owner of the property under the special cohabitation rules (Articles 147 or 148, Family Code), and/or (2) a possessor in good faith entitled to reimbursement for necessary/useful improvements (Civil Code). The “family home” enjoys statutory protection for the benefit of the legal family (spouses or an unmarried head of a family and qualified relatives) and can limit partition or execution while beneficiaries still reside there. Ultimately, heirs can recover possession and partition the estate, subject to: (a) any proven co-ownership share of the live-in partner, (b) family-home protections, and (c) reimbursement/retention rights for improvements made in good faith.

A. Key legal frameworks

1) Succession and co-ownership among heirs

Transmission at death. Successional rights pass from the moment of death (Civil Code, Art. 777).
Estate as co-ownership. Until partition, the estate is held in co-ownership by the heirs (Arts. 1078–1090). Each heir may demand partition, subject to limitations (see Family Home below).
Right to possess. Co-owners each have the right to possess the whole in common and to recover possession from non-owners.

2) Live-in partners and property acquired during cohabitation

Article 147 (both parties free to marry). If the couple were not disqualified to marry each other (no prior subsisting marriage, etc.), wages and properties acquired by their work or industry during cohabitation are co-owned, generally in equal shares absent proof of unequal contributions. Properties acquired by exclusive donation, devise or descent remain exclusive. Bad faith disqualifies the party in bad faith from sharing in profits beyond actual contributions.
Article 148 (one or both parties disqualified to marry). If either party had a subsisting marriage or there’s another impediment, only properties actually acquired by their joint contributions become co-owned, in proportion to proven contributions; no equal-share presumption. Mere cohabitation or contributions in kind (i.e., domestic services) do not automatically create co-ownership in Art. 148 cases.
Important distinctions. These co-ownership rights are property regime rights — not inheritance. A live-in partner does not become an heir by virtue of cohabitation or a void marriage.

3) The Family Home (Family Code, Arts. 152–162)

Deemed constituted. The family home is deemed constituted on the family residence from the time it is occupied as such, without need of judicial or formal constitution.
Beneficiaries. The beneficiaries are the spouses (or an unmarried head of a family) and their parents, ascendants, descendants, brothers and sisters who live in the family home and depend on the head of the family for legal support.
Protection. The family home is exempt from execution except for specific obligations (e.g., taxes, prior debts secured by mortgage, debts incurred for the construction). It also tempers partition while beneficiaries still reside in it.
Continuity after death. The family-home character continues so long as any beneficiary resides therein and the conditions set by law persist (e.g., minor children still living there, or dependent ascendants).
Ownership unaffected. The family-home status does not by itself transfer ownership; it protects the home for qualified beneficiaries against creditors and can delay partition.

4) Possessors and improvements (Civil Code)

Necessary vs. useful vs. luxurious expenses.
- Necessary: preserve the property — reimbursable to a possessor in good faith.
- Useful: increase value or productivity — reimbursable to a possessor in good faith to the extent of increased value.
- Luxurious (ornamental): not reimbursable, but the improver may remove them if it can be done without damage.
Good-faith possessor (Arts. 546–548). Entitled to reimbursement for necessary and useful expenses and has a right of retention until reimbursed. Fruits and rents during good-faith possession generally offset with expenses and improvements.
Builders/planters/sowers on land of another (Art. 448 and related). If in good faith, the landowner typically chooses either to appropriate the improvement with indemnity or to sell the land to the builder, subject to equitable qualifications; bad-faith builders may be compelled to remove or forfeit improvements without indemnity. Jurisprudence tailors these options to fairness (e.g., if land value is greatly disproportionate).

B. Who can stay in the family home after the owner’s death?

If there is a lawful spouse and/or minor/dependent children who are beneficiaries:
- The family-home protection continues for them. Partition or eviction may be deferred while beneficiaries reside and the statutory conditions persist.
- Adult, self-supporting children cease to be beneficiaries when dependency ends.
If the survivor is a live-in partner who is not a legal spouse:
- A live-in partner is not a beneficiary simply by being a partner. Unless they qualify independently (e.g., as an unmarried head of a family supporting qualified relatives who live there) or as a dependent relative of the deceased (rare), family-home protections do not arise in their favor as a partner.
- Their continued stay must rest on ownership (as co-owner under Art. 147/148 or as transferee/tenant) or on tolerance of the heirs.
If the property was acquired during cohabitation and Article 147 applies:
- The live-in partner may be a co-owner (often 50% absent proof of unequal contributions). The heirs succeed only to the decedent’s share. Eviction cannot dispossess a co-owner of their undivided share; remedies shift to partition and accounting.
If Article 148 applies (e.g., the deceased was legally married to someone else during cohabitation):
- The live-in partner must prove actual contributions to claim co-ownership and the extent thereof. Without proof, no share arises from cohabitation alone. The heirs, as owners, may recover possession subject to any established reimbursement rights for improvements in good faith.

C. Heirs’ remedies to recover possession

Demand to vacate / amicable settlement. Often the first step is a written demand asserting inheritance rights and proposing reasonable timelines or buyout options.
Ejectment (unlawful detainer or forcible entry) in first-level courts.
- Unlawful detainer applies if the live-in partner’s initial possession was lawful or by tolerance (e.g., as cohabitant) but became illegal upon demand to vacate.
- This is summary; it addresses possession (physical), not full ownership. If ownership issues are raised, the court may look into them only to resolve possession.
Acción reivindicatoria / recovery of ownership and possession.
- When title and dominion must be resolved (e.g., a serious Article 147/148 co-ownership claim or complex improvements), heirs may sue in the Regional Trial Court for recovery of ownership, possession, partition, and accounting.
Partition and accounting among heirs (and any proven co-owner).
- If the live-in partner proves co-ownership, the proper route is to partition and settle fruits, expenses, and reimbursement issues.
- Partition may be deferred while family-home beneficiaries continue to reside under law.

D. Reimbursement for improvements by a live-in partner

1) When the partner is a co-owner (Art. 147/148)

Co-owner improvements without consent. A co-owner who funds necessary or useful improvements may seek reimbursement proportionate to co-owners’ shares, subject to rules on acts of administration vs. alteration of the common property.
Accounting at partition. Reimbursements and betterments are typically settled in the accounting phase, with equitable adjustments (e.g., awarding the improved portion to the co-owner who paid for it, with owelty/cash equalization).

2) When the partner is not a co-owner but a good-faith possessor

Necessary and useful expenses (Arts. 546–548). The partner may recover:
- Necessary expenses in full; and
- Useful expenses to the extent of the increase in value.
Right of retention. The possessor in good faith may retain the property until reimbursed. Good faith generally ceases once the possessor knows their title is defective (e.g., receipt of a demand or service of a complaint).
Luxurious/ornamental expenses. No reimbursement, but the possessor may remove them if feasible without damage.

3) “Builder in good faith” (Art. 448 and related)

When the partner built or substantially improved in good faith on land later adjudged to belong to the heirs/estate:
- The landowner typically chooses to appropriate the improvement with indemnity (usually necessary/useful expenses or the value added) or to sell the land to the builder, subject to equitable limits if values are grossly disproportionate.
- If the builder is in bad faith, the owner may demand removal at the builder’s expense and/or forfeiture without indemnity (subject to equitable considerations).

E. Determining “good faith” and burden of proof

Good faith means honest belief in one’s right to possess or build, without knowledge of any flaw in title.
Burden of proof:
- The live-in partner claiming co-ownership bears the burden to prove the case fits Art. 147 or 148 and, for Art. 148, the actual contributions.
- The partner claiming reimbursement must prove the nature of expenses, their necessity or utility, and the increase in value for useful expenses (receipts, contractor reports, appraisals, photos, testimony).
Cessation of good faith: Typically from demand or service of summons, the possessor can no longer claim fruits; subsequent expenditures risk being treated as in bad faith (no right of retention beyond necessary expenses).

F. Interaction between the Family Home and heirs’ rights

If qualified beneficiaries still reside:
- Execution and partition may be limited or deferred; heirs cannot simply eject qualified beneficiaries to hasten partition.
- The home may still be alienated by the owner(s), but protections follow the statutory scheme.
If no qualified beneficiaries remain (or conditions cease):
- Family-home protection ceases; heirs may proceed to partition, ejectment, or recovery of possession, subject to other rights (e.g., a partner’s co-ownership or reimbursement claims).
Tax dimension (estate settlement).
- For estate tax purposes, the family home deduction (currently up to ₱10,000,000 under the TRAIN law) may apply when computing the taxable estate, but this affects taxation — not civil ownership or possessory rights.

G. Practical playbook for heirs

Title and fact-finding. Secure the title/tax declarations, verify acquisition dates, and determine whether the property was acquired during cohabitation and which article (147/148) applies.
Assess beneficiaries. Identify qualified family-home beneficiaries presently living there (lawful spouse, minor/dependent children, dependent ascendants/siblings).
Document possession and improvements. Inventory the improvements the partner claims (receipts, before-and-after photos, appraisals).
Make a calibrated demand. Send a demand letter: offer mediation, propose buyout/lease arrangements, or set conditions (e.g., accounting and partition).
Choose the forum strategically.
- Ejectment for immediate possessory relief when the partner had only tolerated possession and no substantial ownership issues.
- Reivindicatory/partition action in the RTC when ownership/co-ownership or Art. 147/148 claims and improvements will be litigated.
Prepare for reimbursement/retention. Budget for necessary/useful expense reimbursement if the partner shows good faith; anticipate a right of retention defense.

H. Practical playbook for a live-in partner in occupation

Clarify your legal footing. Determine if your case is Art. 147 (both free to marry) or Art. 148 (with impediment). Gather proof of contributions (cash flows, payroll, remittances, materials, labor, opportunity cost).
Prove good faith. Keep evidence showing you honestly believed you could possess or build (e.g., permission, contributions, agreements, lack of adverse claims).
Catalog improvements. Classify expenses as necessary, useful, or luxurious; obtain appraisals for the value added by useful improvements.
Consider settlement options. Explore buyout, co-ownership partition, or leaseback. Asserting a right of retention can be a bargaining chip — but only when backed by good-faith improvements.

I. Common scenarios and likely outcomes

Property titled solely to the deceased; cohabitation under Art. 148; no proof of contribution. Likely no co-ownership for the partner. Heirs can recover possession; partner may claim reimbursement for necessary/useful improvements made in good faith, with possible retention until paid.
Property acquired during Art. 147 cohabitation; partner contributed money/work. Presumed co-ownership (often 50–50 absent proof otherwise). Heirs only succeed to the decedent’s share. Outcome is typically partition and accounting, not eviction.
Lawful spouse and minor children still living in the home. Family-home protection continues; partition and recovery may be deferred while beneficiaries reside. A non-beneficiary partner’s possession claims give way to the beneficiaries’ protective mantle, subject to co-ownership (if any) and reimbursement issues.
Partner built a significant addition believing in ownership (good faith). Expect application of Art. 448 principles: indemnity vs. sale options, or equitable rent, depending on relative values and equities.

J. Evidence and litigation tips

Paper trail rules the day. Titles, deeds, bank records, receipts, contractor agreements, photos, and expert valuation are decisive.
Chronology matters. Show when the relationship began, when the property was acquired, when construction occurred, and when the partner learned of competing claims (good-faith cutoff).
Mind the remedy’s scope. Ejectment is for possession; reivindicatory actions settle ownership and improvements in full.
Account for fruits and offsets. Useful fruits/rents enjoyed during good-faith possession may be offset by reimbursable expenses; bad-faith possession can trigger liability for fruits and damages.

K. Checklist for counsel

Identify heirs and shares; confirm title history.
Determine Art. 147 vs. 148, and gather contribution evidence.
Verify family-home beneficiaries and continuing residency/dependency.
Catalog improvements and classify expenses; obtain appraisal of value added.
Evaluate good faith timeline; preserve demand letters/service dates.
Choose ejectment vs. reivindicatory/partition, aligning with goals and evidence.
Budget for reimbursement/retention exposure or leverage.
Consider mediation for structured buyout/partition with timelines.

Closing note

This article synthesizes core doctrines under the Civil Code and the Family Code (Arts. 152–162 on the family home; Arts. 147–148 on cohabitation), together with settled principles on possessors and builders in good/bad faith. Specific outcomes turn on proof (co-ownership under 147/148; good-faith improvements; existence of qualified family-home beneficiaries). In disputes, expect courts to balance heirs’ succession rights, family-home protections, and equitable indemnity for good-faith improvements.