Here’s a practical, no-nonsense explainer you can rely on for the Philippine setting. It covers what each remedy is, exact grounds, who can file and when, how the court process works, effects on property and children, and the real-world costs and timelines.

Annulment vs. Declaration of Nullity (Philippines)

Big picture

Declaration of Absolute Nullity of Marriage (“nullity”) ends a void marriage—i.e., a marriage that was never valid from the start (void ab initio).
Annulment ends a voidable marriage—i.e., a marriage that was valid when celebrated but can be set aside due to specific defects affecting consent or capacity.

Topic	Declaration of Nullity (void marriage)	Annulment (voidable marriage)
Legal idea	Marriage never existed in law	Marriage existed but is set aside
Filing deadline	Imprescriptible (no time bar)	Strict deadlines (varies by ground; see below)
Typical grounds	No essential/formal requisite; bigamy; lack of license (no exception); psychological incapacity; incest/prohibited degrees; mistake in identity; etc.	Lack of parental consent (18–21 yrs), unsound mind, fraud, force/intimidation/undue influence, impotence (incurable), serious & apparently incurable sexually transmissible disease
Children’s status	Generally illegitimate; exception: if the ground is psychological incapacity (Art. 36), children conceived/born before finality are legitimate	Legitimate
Property regime while “married”	Co-ownership rules (Arts. 147/148) apply, not conjugal/ACP	Conjugal Partnership or Absolute Community dissolves and is liquidated
Remarriage	Allowed only after finality and civil registry annotation (Art. 52/53 compliance)	Same

In Philippine civil law, there’s no general divorce (outside Muslim personal law and certain foreign-divorce scenarios). For most, the only ways to sever the marital bond are nullity or annulment.

Grounds (exhaustive, with plain-English notes)

A. Grounds for Declaration of Nullity (void marriages)

Below 18 at marriage (even with consent).
No authority of the solemnizing officer and no good-faith belief in such authority.
No marriage license, and no valid exception (e.g., 5-year cohabitation; in articulo mortis; remote areas; etc.).
Bigamous/polygamous marriage (except when the first spouse is judicially declared presumptively dead under Art. 41 before the second marriage).
Mistake as to identity of a party.
Psychological incapacity (Art. 36): A legal—not medical—concept. It refers to serious, antecedent, and incurable personality dispositions that render a spouse truly unable to assume essential marital obligations. A clinical diagnosis is not strictly required; expert testimony can help but isn’t indispensable.
Incestuous marriages (ascendants/descendants; full/half siblings).
Marriages void for public policy (e.g., within certain degrees of consanguinity/affinity; adoptive relations; step-relations; where a party killed the other’s spouse, etc.).
Subsequent marriage void under Art. 53 for failure to record a prior decree/property liquidation/children’s presumptive legitimes as required by Art. 52 before remarrying.

Key reminders on psychological incapacity: Courts emphasize the gravity, juridical antecedence (existing at or before marriage), and incurability. It isn’t mere difficulty, incompatibility, immaturity, or refusal to do chores.

B. Grounds for Annulment (voidable marriages)

A marriage valid at the start can be annulled for:

Lack of parental consent (party was 18–21 at marriage):
- Who can file: the party (within 5 years after turning 21) or the parent/guardian before the party turns 21.
- Ratification: Free cohabitation after 21 bars this ground.
Unsound mind (at marriage):
- Who can file: the sane spouse who didn’t know, or relatives/guardian of the incapacitated spouse; within 5 years after regaining sanity or after discovery.
Fraud (must be one of the law-listed frauds), e.g.:
- Concealment of a previous conviction for a crime involving moral turpitude;
- Concealment by the wife of pregnancy by another man at the time of marriage;
- Concealment of drug addiction, habitual alcoholism, homosexuality or lesbianism existing at the time;
- Concealment of an STD existing at the time (even if curable, as fraud).
- Filing deadline: Within 5 years from discovery of the fraud.
- Ratification: Free cohabitation after discovery bars the ground.
Force, intimidation, undue influence:
- Filing deadline: Within 5 years from the time it ceased.
- Ratification: Free cohabitation after the coercion ends bars the ground.
Incurable impotence (physical incapacity to consummate with the other spouse; existing at marriage, continuing, and appears incurable):
- Filing deadline: Within 5 years from the marriage.
Serious & apparently incurable STD (existing at marriage):
- Filing deadline: Within 5 years from the marriage.

Who can file, venue, and parties

Who files: A spouse (or, in limited cases, parents/guardians/relatives as above).
Venue: Family Court (RTC) of the province/city where the petitioner or respondent has resided for at least 6 months immediately before filing; if the respondent is non-resident, where the petitioner resides.
State participation: The Public Prosecutor must investigate possible collusion. The Office of the Solicitor General (OSG) represents the State and can oppose and appeal.

Procedure—what actually happens

Prepare & file a verified petition (with Certification against Forum Shopping). Attach: PSA marriage cert, children’s PSA birth certs, IDs, proof of residence, evidence (e.g., psychological report for Art. 36; medical proofs; sworn witness statements; proof of bigamy; etc.).
Raffle to a Family Court; summons issued to the other spouse.
Collusion investigation by the Prosecutor (mandatory).
Pre-trial: Narrow the issues; settle incidental matters (custody, support, visitation, interim property arrangements). No compromise on the marital status itself.
Trial: Petitioner’s testimony; corroborating witnesses; experts (as needed). Respondent and the State can cross-examine and present evidence.
Memoranda (written arguments), then Decision: petition granted or denied.
Appeal window (typically 15 days). The OSG often appeals in granted cases.
Finality: If unappealed or affirmed on appeal, judgment becomes final & executory.
Registration/Annotation (critical): The court directs the Local Civil Registrar and PSA to record the decree (and, where required, property liquidation and delivery of presumptive legitimes).
- No remarriage until these are done; a subsequent marriage without Art. 52/53 compliance is void.
Post-judgment matters: Liquidation of property regime; settlement of support/custody; tax and title transfers as needed.

Evidence you’ll typically need

Nullity (void)
- Art. 36 (psychological incapacity): Spousal history, patterns of incapacity, witness accounts (family/friends), documentary trail (messages, records), and often a psychological evaluation (not mandatory by law, but persuasive).
- Bigamy: Prior subsisting marriage records; absence of valid termination; or lack of judicial presumptive-death declaration before the second marriage.
- No license/authority: Civil registry certifications; proof that an exception does not apply; details on the officiant.
- Prohibited relationships: Birth records, family tree, adoption decrees.
Annulment (voidable)
- Fraud: Proof of the specific statutory fraud (e.g., conviction records; medical records; proof of pregnancy by another).
- Force/intimidation: Threats, police blotters, messages, witness testimony.
- Impotence/STD: Medical evidence; expert opinion.

Effects of a granted petition

Civil status & names

The marital tie is severed (or declared never to have existed). A woman may revert to her maiden name. PSA records get annotated.

Children

Annulment: Children remain legitimate.
Nullity: Children are generally illegitimate, except those conceived/born before finality in Art. 36 (psychological incapacity) cases, who are treated as legitimate.
Custody & support: Determined by the court based on best interests of the child. Support obligations continue.

Property

Nullity: Apply Art. 147 (both parties free to marry each other; co-ownership—typically equal shares unless proven otherwise, including non-monetary contributions) or Art. 148 (where one/both were disqualified to marry—e.g., bigamy; shares are based on actual proven contributions; no share from illicit/unlawful consideration).
Annulment: The Absolute Community or Conjugal Partnership is dissolved and liquidated. The court orders delivery of children’s presumptive legitimes and addresses support/custody.

Criminal & other consequences

Bigamy (criminal) is distinct from civil nullity; timelines and defenses differ.
Perjury, falsification, or sham cases risk sanctions. Always proceed in good faith.

Cost: what people actually spend (Philippine practice)

There’s no official “fixed price.” Budgets vary by city, facts, number of hearings, and whether the OSG appeals. Typical components:

Attorney’s fees: ~ ₱150,000–₱500,000+ (complex, contested, or appealed cases can exceed this).
Psychological evaluation (if pursuing Art. 36): ~ ₱25,000–₱100,000+ per party/witness, depending on the expert and scope.
Court fees & sheriff’s fees: ~ ₱5,000–₱20,000+ (location-dependent).
Publication/service by publication (if respondent unlocatable): ~ ₱15,000–₱40,000+.
Misc. (copies, notarial, transcripts, transport, titles): budget ₱10,000–₱50,000+.

Strategy tip: Strong, well-organized evidence can shorten trial time and cost. Weak or scattershot claims (especially for Art. 36) often lead to denials or lengthy appeals.

Timelines (realistic expectations)

Uncontested, straightforward: ~ 1–2 years to a trial court decision.
Contested / complex facts / OSG appeal: 2–4+ years to finality.
Post-judgment annotation with PSA: add a few months.
You cannot remarry until the decree (and required property/children orders) are properly recorded.

Common pitfalls & how to avoid them

Calling everything “annulment.” Use the right remedy: nullity (void) vs. annulment (voidable).
Thin Art. 36 claims. Courts look for serious, antecedent, incurable incapacity—not mere incompatibility.
Skipping Art. 52/53 compliance. Failure to record the decree (and required instruments) voids a subsequent marriage.
Assuming a church decree is enough. Canon (church) annulments don’t change civil status; you still need a civil case.
Foreign divorce confusion. If your foreign spouse validly divorces you abroad (or your Filipino spouse later became foreign and divorced abroad), you likely need a judicial recognition of that foreign judgment here—not an annulment/nullity case.

Alternatives you should know

Legal Separation: Ends cohabitation and dissolves property regime, but does not dissolve the marital bond (no remarriage).
Judicial Recognition of Foreign Divorce: If eligible under Art. 26(2), quicker than annulment/nullity.
Summary Declaration of Presumptive Death: For truly missing spouses (strict conditions) before contracting a new marriage.

Step-by-step checklist (practical)

Identify the correct ground (void vs. voidable).
Map the evidence you already have vs. what you must obtain.
Budget for counsel, experts, and court costs.
Hire counsel (family-law experience matters).
Draft, verify, file the petition with complete annexes.
Attend collusion investigation, pre-trial, then trial.
If granted, monitor appeals and, after finality, push the annotations with LCR/PSA.
Complete property liquidation and update IDs/titles.
Only then consider remarriage.

Quick FAQs

Can I file anywhere? No—there are venue rules tied to residence.
Do I need a psychologist for Art. 36? Not strictly required, but often persuasive; quality matters more than labels.
Will I automatically lose custody? No. Custody is based on the child’s best interests; courts can order support/visitation.
Can we “settle” the marriage status? No. Status of persons cannot be compromised; only ancillary issues can be settled.
After a grant, can I use my maiden name? Yes—you may revert and update your IDs once records are annotated.

Disclaimer: This is general information for the Philippine legal framework. Specific facts can change outcomes. For tailored advice and document review, consult a Philippine family-law practitioner.