Quick answer

Both legitimate and illegitimate children can inherit from their parents in the Philippines. Both are compulsory heirs, meaning a parent generally cannot use a will to deprive them of the minimum share reserved by law, called the legitime.

The principal difference is the size of the share:

A legitimate child ordinarily receives twice the share of an illegitimate child when they inherit together.
Under Article 176 of the Family Code, the legitime of each illegitimate child is one-half of the legitime of each legitimate child.
If there is no will and legitimate and illegitimate children inherit together, the same 2:1 proportion generally applies.
If only illegitimate children survive and there are no competing heirs whose rights the law protects, they may inherit the entire net estate in equal shares.

These are starting rules, not automatic final computations. The actual shares depend on whether there is a valid will, a surviving spouse, predeceased children or grandchildren, adopted or legitimated children, lifetime donations, estate debts, and proof of filiation.

What property is actually divided among the heirs?

Inheritance is computed from the deceased person’s estate—not automatically from every asset associated with the family.

Before shares are calculated, the estate usually must be determined by:

Identifying which assets belonged to the deceased.
Liquidating the spouses’ absolute community or conjugal partnership, when applicable.
Separating the surviving spouse’s own share from the deceased spouse’s share.
Accounting for enforceable debts, taxes, expenses, and other lawful charges.
Considering lifetime donations that may be subject to collation or reduction.
Identifying assets that pass under a separate legal arrangement, such as certain insurance or employment benefits payable directly to named or statutory beneficiaries.

The remaining amount is the net hereditary estate used to compute inheritance. A percentage applied to the gross value of a family home or jointly held property can therefore produce a seriously inaccurate result.

Successional rights generally arise at the moment of death under Article 777 of the Civil Code, although ownership, taxes, administration, and registration may still have to be settled.

Who is considered a legitimate or illegitimate child?

Under the Family Code, children conceived or born during a valid marriage are generally legitimate. The Code also recognizes specific situations in which children remain legitimate despite annulment or nullity proceedings.

Children conceived and born outside a valid marriage are generally classified by statute as illegitimate, subject to the Family Code’s exceptions. “Nonmarital child” is often used as a less stigmatizing description, but “illegitimate child” remains the term appearing in the governing statutes.

A child who is validly legitimated by the parents’ subsequent marriage enjoys the same rights as a legitimate child. Legitimation is available only when the statutory requirements are met; the parents’ later marriage alone should not be assumed to cure every situation.

An adoptee is treated as the legitimate child of the adopter. Sections 41 and 43 of the Domestic Administrative Adoption and Alternative Child Care Act give adopter and adoptee reciprocal succession rights without distinction from legitimate filiation. The consequences for succession through biological relatives require separate analysis because adoption generally severs the legal ties with biological parents, except in specified cases such as step-parent adoption.

Rights when the parent left a valid will

A person may decide through a will who receives the freely disposable part of the estate. That freedom is limited by the legitimes of compulsory heirs.

Legitimate children

Under Article 888 of the Civil Code, the collective legitime of legitimate children and descendants is generally one-half of the hereditary estate, divided among them according to the rules on succession.

For example, if two legitimate children are the only compulsory heirs, their collective legitime is one-half of the estate. Each child’s individual legitime is ordinarily one-fourth. The other half is initially the free portion, subject to other compulsory heirs and valid testamentary dispositions.

Illegitimate children

Article 176 of the Family Code provides that the legitime of each illegitimate child is one-half of the legitime of a legitimate child.

When legitimate and illegitimate children survive together, the illegitimate children’s legitimes are ordinarily charged against the disposable portion. Their total legitimes cannot exceed that portion, and the surviving spouse’s legitime must first be fully protected where applicable.

If there are no legitimate children or descendants, Article 901 of the Civil Code generally reserves one-half of the estate collectively for the illegitimate children, subject to the rights of other compulsory heirs.

A will cannot simply erase a child’s legitime

A statement such as “I leave nothing to my son” does not by itself validly disinherit a compulsory heir. Disinheritance must be made in a will, must identify a cause expressly recognized by law, and must comply with the Civil Code’s requirements. The person relying on the disinheritance may have to prove the stated cause if it is contested.

If a compulsory child or descendant is completely and unintentionally omitted from a will, the rules on preterition may apply. Article 854 provides that preterition of a compulsory heir in the direct line can annul the institution of heirs, while preserving devises and legacies only insofar as they do not impair legitimes. The effect depends on the language of the will and whether the omission was total.

Rights when there is no will

When there is no valid will—or when a will does not dispose of the entire estate—the Civil Code’s intestate-succession rules determine the heirs and their proportions.

Legitimate and illegitimate children together

Article 983 directs that the illegitimate children’s shares follow the proportion stated in Article 895. In ordinary terms:

Each legitimate child receives two units.
Each illegitimate child receives one unit.

Suppose the deceased left no spouse and was survived by two legitimate children and one illegitimate child. The estate is divided into five units:

Legitimate child 1: 2/5
Legitimate child 2: 2/5
Illegitimate child: 1/5

This example assumes established filiation, no representative descendants, and no other fact changing the computation.

Children and a surviving spouse

If a surviving spouse inherits together with legitimate and illegitimate children, Articles 996, 999, and 983 generally give the spouse a share equal to that of one legitimate child.

For example, if the heirs are one legitimate child, one illegitimate child, and the surviving spouse, the usual proportional weights are:

Legitimate child: two units
Surviving spouse: two units
Illegitimate child: one unit

The resulting shares are ordinarily 2/5, 2/5, and 1/5, respectively, after first separating the surviving spouse’s ownership in community or conjugal property.

If only a surviving spouse and illegitimate children remain, Article 998 generally gives:

One-half to the surviving spouse
One-half collectively to the illegitimate children or their qualifying descendants

Only illegitimate children

Under Article 988, illegitimate children succeed to the entire estate when there are no legitimate descendants or ascendants and no competing heir whose rights alter the distribution. Children in the same degree generally divide their collective share equally.

Illegitimate children and legitimate ascendants

If the deceased left legitimate parents or other qualifying legitimate ascendants but no legitimate descendants, Article 991 generally assigns:

One-half of the estate to the legitimate ascendants
One-half collectively to the illegitimate children

If a surviving spouse is also present, Article 1000 supplies a different division: one-half to the legitimate ascendants, one-fourth to the spouse, and one-fourth collectively to the illegitimate children.

What happens when a child dies before the parent?

The right of representation may allow a deceased child’s descendants to receive the share that the child would have inherited. It does not apply in every situation—for example, a person who merely renounces an inheritance generally cannot be represented on that basis.

A major recent clarification concerns nonmarital grandchildren. In Aquino v. Aquino, G.R. Nos. 208912 and 209018, the Supreme Court held that children, regardless of the circumstances of their birth, may represent their predeceased parent in the estate of a direct ascendant, such as a grandparent. The ruling specifically concerns inheritance in the direct line by right of representation and does not broadly erase every statutory restriction involving collateral relatives. See the Supreme Court decision in Aquino and the Court’s official case summary.

Because representation depends on the family tree, dates of death, and each person’s legally established filiation, multigenerational estates should be computed branch by branch.

The remaining restriction involving legitimate relatives

Article 992 of the Civil Code still states that an illegitimate child may not inherit by intestacy from the legitimate children and relatives of that child’s father or mother, and vice versa. This is commonly called the “iron curtain” rule.

The rule must now be read together with Aquino. It does not prevent a nonmarital child from representing a predeceased parent in the intestate estate of a direct ascendant when the requirements for representation are met. However, Aquino expressly did not decide all situations involving inheritance in one’s own right from collateral relatives.

Claims involving grandparents, siblings, half-siblings, aunts, uncles, nephews, nieces, or cousins should therefore not be decided from Article 992 alone. The direct or collateral line, the status of the connecting relative, and whether the claimant inherits personally or by representation can change the answer.

Filiation must be proved

Biological relationship asserted informally within a family is not always enough to support a legal claim against an estate. The child must establish the required filiation.

Under Articles 172 and 175 of the Family Code, relevant proof may include:

A record of birth appearing in the civil register
A final judgment establishing filiation
An admission of filiation in a public document
A private handwritten instrument signed by the parent
Open and continuous possession of the status of the parent’s child
Other evidence allowed by the Rules of Court and special laws

The weight of a birth certificate depends on how it was prepared, what it states, and whether the alleged parent made or authenticated the relevant acknowledgment. Using the father’s surname under Republic Act No. 9255 can be relevant but should not be treated as a substitute for examining the acknowledgment and supporting records.

For a person governed by the Family Code, an action based on open and continuous possession of status or other secondary evidence generally must be brought during the alleged parent’s lifetime. Different periods may apply when the claim rests on a civil-registry record, judgment, or written admission. People born before the Family Code took effect may also have vested rights governed by earlier law, as illustrated by Aquino.

Because waiting for the alleged parent to die can eliminate an available ground or make proof much harder, disputed paternal filiation requires prompt legal advice.

Practical steps after a parent dies

1. Preserve the estate before discussing percentages

Secure copies of titles, tax declarations, bank and investment records, business documents, vehicle registrations, insurance policies, loan papers, and evidence of the deceased’s ownership. Do not transfer, withdraw, sell, or conceal assets merely because one heir has physical access to them.

2. Obtain civil-status records

Collect Philippine Statistics Authority or local civil-registry copies of:

The deceased’s death certificate
Each child’s birth certificate
The parents’ marriage certificate, if any
Annulment, nullity, recognition, legitimation, or adoption records
Death certificates of children who died before the deceased

Check names, dates, annotations, and signatures for inconsistencies.

3. Locate the original will

A will cannot simply be ignored because the family prefers an extrajudicial arrangement. Under Rule 75, no will passes property unless it is proved and allowed in the proper court. Preserve the original and obtain advice about probate.

4. Prepare a complete family tree

List every child, including children from prior relationships, children living abroad, adopted or legitimated children, and children who predeceased the parent. For a deceased child, list all descendants who may represent that branch.

5. Prepare an estate inventory

Identify the ownership history and source of each asset. Note whether it was acquired before marriage, during marriage, by inheritance, or by donation. Record mortgages, unpaid taxes, business liabilities, and claims against the deceased.

6. Determine the proper settlement procedure

An extrajudicial settlement under Rule 74 of the Rules of Court is generally available only if:

The deceased left no will;
The estate has no debts;
All heirs participate;
Adult heirs act for themselves; and
Minors are represented by representatives duly authorized for that purpose.

The agreement must be in a public instrument and comply with filing, publication, bond, tax, and registration requirements. The required notice is published once a week for three consecutive weeks. Publication does not make a settlement binding on an heir who neither participated nor had notice.

If heirs disagree, filiation is contested, an heir is missing, a will exists, debts remain, or administration is needed, judicial proceedings may be necessary.

7. Address estate tax promptly

The BIR estate-tax return is generally due within one year from the date of death. A filing extension of no more than 30 days may be granted in meritorious cases, but it should not be assumed. Payment arrangements and requirements depend on the estate’s circumstances.

Consult the BIR estate-tax page, the official BIR Form 1801 guidelines, and current BIR issuances. Tax compliance does not determine who the lawful heirs are; it is a separate obligation in settling and transferring the estate.

Evidence worth preserving

Where filiation or inclusion in the estate may be disputed, preserve originals or authenticated copies of:

Birth and baptismal records
Written acknowledgments signed by the parent
Affidavits of admission of paternity
Letters, cards, emails, and messages identifying the child
School, medical, insurance, employment, and government records naming the parent
Proof of regular support, tuition, housing, or medical payments
Photographs and family records showing sustained treatment as a child
Court decisions and civil-registry annotations
DNA evidence or information identifying suitable relatives for possible lawful testing
Existing pleadings, settlement documents, notices, and publication records
Proof that the claimant participated—or was excluded—from estate proceedings

Keep the original electronic files where possible. Screenshots alone may omit dates, account information, or other details needed to authenticate a communication.

Common mistakes

Computing shares from the gross property without first liquidating the marital property regime.
Assuming that “illegitimate” means the child has no inheritance rights.
Dividing everything equally despite the statutory 2:1 proportion.
Treating the name on a birth certificate as conclusive without checking its execution and authenticity.
Excluding a child because the parents never lived together or because the child uses the mother’s surname.
Assuming that a parent may disinherit a child for any personal reason.
Ignoring lifetime donations that may affect collation or impair a legitime.
Signing an extrajudicial settlement that fails to disclose every heir.
Selling estate property before authority, taxes, and ownership are settled.
Believing that newspaper publication cures the exclusion of a known heir.
Treating Rule 74’s two-year period as a universal deadline that automatically destroys every omitted heir’s claim.
Delaying a filiation case until after the alleged parent dies.
Ignoring a will instead of submitting it for probate.

When legal help is urgent

Consult a Philippine succession lawyer promptly if:

An estate-tax deadline is approaching.
Property is being sold, mortgaged, withdrawn, or transferred without all heirs’ authority.
A child was omitted from a will or settlement.
Paternity or maternity is denied or the civil records conflict.
The alleged parent is still alive but seriously ill and filiation is not formally documented.
A minor, incapacitated person, missing heir, or heir abroad is involved.
Someone asks an heir to sign a waiver, quitclaim, deed of sale, or extrajudicial settlement without a complete inventory and share computation.
A will appears altered, hidden, forged, or executed under pressure.
The estate involves several marriages, overlapping relationships, adoption, legitimation, or predeceased children.
Titles have already been transferred based on a settlement that omitted an heir.

Immediate court relief may be needed when assets are at risk of dissipation. The appropriate remedy depends on the documents and procedural history.

Frequently asked questions

Can an illegitimate child inherit from both parents?

Yes, provided filiation to each parent is legally established and no particular statutory restriction applies. Proof of maternity is usually straightforward from the birth record; disputed paternity often requires closer examination.

Is the illegitimate child always entitled to exactly half of the estate?

No. “One-half” usually describes the relationship between the illegitimate child’s legitime and the legitimate child’s legitime—not one-half of the entire estate. The final fraction depends on the number and classes of heirs.

Do children from different marriages inherit equally?

Legitimate children in the same degree generally inherit equally from their common parent. Their mothers’ identities or the order of the marriages do not create larger or smaller shares. An illegitimate child inheriting with them ordinarily receives half the share of each legitimate child.

Can a child inherit even if the parent gave no support?

Possibly. Failure to provide support does not by itself erase filiation or the child’s successional rights.

Can a parent leave everything to only one legitimate child?

Not ordinarily. A will may favor one child only within the disposable portion and cannot impair the other compulsory heirs’ legitimes, absent valid disinheritance.

Can an illegitimate grandchild inherit from a grandparent?

Yes, in appropriate cases by representing a predeceased parent. Aquino v. Aquino confirms that birth status alone does not disqualify a child from representing a parent in the estate of a direct ascendant. The parent must have predeceased or otherwise fall within a situation where representation is legally allowed, and the connecting filiation must be proved.

Does carrying the father’s surname automatically prove inheritance rights?

No. It may support the claim, but the underlying acknowledgment, civil-registry documents, and other evidence must still be examined under the Family Code and Republic Act No. 9255.

Can heirs agree to equal shares despite the legal proportions?

Adult heirs may enter lawful arrangements concerning rights they can validly dispose of, but the transaction must be informed, voluntary, properly documented, and compliant with rules protecting minors, creditors, taxes, and third parties. A supposed “agreement” obtained through concealment, mistake, intimidation, or exclusion can be challenged.

Does an illegitimate child inherit from a half-sibling?

Not automatically. Intestate inheritance across legitimate and illegitimate collateral lines raises Article 992 issues that Aquino did not fully resolve. The exact family relationships and the source of the claimed right must be reviewed.

Is there one deadline for claiming an inheritance?

No. Different periods may apply to filiation actions, probate remedies, actions involving fraud or excluded heirs, recovery of property, estate-tax filing, and claims under Rule 74. The two-year period associated with an extrajudicial settlement is not a universal bar against every omitted heir, particularly one who did not participate or have notice.

Official legal sources

This article provides general legal information, not legal advice or a definitive computation for a particular estate. Succession outcomes depend on the will, civil-status documents, dates, family tree, property regime, debts, donations, and procedural history. Official sources were checked for currency on September 4, 2026.