Short answer. It comes out of the free portion — the part of the estate the deceased could have given to anyone. Two limits apply: the surviving spouse's legitime must be fully satisfied first, and the illegitimate children's total legitime can never exceed that free portion.
What the law says
The legitime of the illegitimate children shall be taken from the portion of the estate at the free disposal of the testator, provided that in no case shall the total legitime of such illegitimate children exceed that free portion, and that the legitime of the surviving spouse must first be fully satisfied.
Civil Code, Article 895 — Legitime by the Old Sub-Classes. Read the full provision →
Read the size rule from the Family Code, not from this article
Article 895 of the Civil Code still contains the rule on where the share is taken from, and that part is the answer to this question. But its opening paragraphs — the graduated scheme separating acknowledged natural children, natural children by legal fiction, and other illegitimate children into fractions of one another — have been superseded by the Family Code.
Under the Family Code there are no sub-classes. Every illegitimate child has a legitime equal to one-half of the legitime of a legitimate child, full stop. If a source or a computation you have been given uses four-fifths of an acknowledged natural child's share, it is working from the old scheme and the figure is wrong.
How the estate is carved up, in order
Start with the whole estate after debts. Set aside the legitime of the legitimate children — the portion the law reserves for them, which the deceased could not give away. What remains is the free portion.
From that free portion, the surviving spouse's legitime is satisfied first. The article says so in terms. Only what is left after the widow or widower has been fully paid is available to answer for the illegitimate children's legitime. This ordering is why a widow's share is not reduced to accommodate an illegitimate child — the reduction, if any, falls on the illegitimate side.
When the free portion is not enough
This is the situation that generates most family disputes. Where there are several legitimate children and a surviving spouse, the free portion can be small. The article caps the illegitimate children's total legitime at that free portion — it cannot spill over into the legitimate children's reserved share.
The practical consequence is that illegitimate children may receive less than the one-half formula would suggest, and they share proportionally in whatever the free portion can carry. The formula sets the ceiling; the free portion sets the reality. Nothing is left over for voluntary legacies once the free portion is exhausted this way.
What this means for your own family situation
Two things decide these cases before any arithmetic starts. The first is filiation — whether the child's relationship to the deceased is established by the record of birth, an admission in a public document, a signed private handwritten instrument, or the other proof the law allows. Without that, there is no legitime to compute.
The second is the property regime of the marriage. What the deceased actually owned is only his share of the conjugal or community property, and getting that step wrong distorts everything after it. Nobody can promise a particular outcome from a formula alone. Gather the birth records, the marriage certificate, the titles and the list of debts, and have the computation done by a lawyer on the real numbers.
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.
- Elenita V. Macalinao, Kenneth V. Macalinao and Kristel V. Macalinao vs. Cerina, A.K.A. Cerena N. Macalinao and Cindy N. Ma, G.R. No. 250613, April 3, 2024 — read the decision on LawPhil →
- Daniel Rivera and Elpidio Rivera vs. Flora P. Villanueva, Ruperto Pacheco, Virgilio Pacheco, G.R. No. 197310, June 23, 2021 — read the decision on LawPhil →
- Eloy Imperial vs. Court of Appeals & Cesar Villalon, etc., et al, G.R. No. 112483, October 8, 1999 — read the decision on LawPhil →