Short answer. Under Article 12 of the Civil Code, a custom must be proved as a fact according to the rules of evidence. It is not taken for granted simply because you assert it. The party invoking a custom bears the burden of establishing it through testimony, documents, or other admissible proof.
What the law says
A custom must be proved as a fact, according to the rules of evidence.
Civil Code, Article 12 — Custom Must Be Proved. Read the full provision →
Custom is not self-proving
Article 12 of the Civil Code states plainly: "A custom must be proved as a fact, according to the rules of evidence." This is a foundational rule that applies whenever a party to a dispute invokes local practice, trade usage, or community custom to support a legal position. Courts do not take judicial notice of customs the way they take notice of statutes. No matter how widespread or well-known you believe the practice to be, you must introduce proof of it at trial or in proceedings the same way you would prove any other contested fact.
What makes something a legally recognized custom
The Civil Code recognizes custom as a source of law when it is not contrary to law, public order, or public policy. But before a custom can have any legal effect, it must first be established that it actually exists. Legal usage in the Philippines generally requires showing that a practice is general, well-settled, uniform, and generally known within a particular place or trade. A single instance of a practice, or one that is contested within the community, would not rise to the level of a recognized custom — it must have sufficient prevalence and consistency to qualify.
How to prove a custom in practice
Because a custom is proved "according to the rules of evidence," the standard tools of litigation apply. Testimony from multiple witnesses who can speak from personal knowledge of the practice is one common method — particularly people with long experience in the relevant trade, locality, or industry. Written records that reflect consistent use of the practice over time can also help. In commercial disputes, a custom or usage of trade may be established through trade publications, affidavits from industry participants, or expert testimony about established practices in the field. The goal is to show that the practice is objectively settled, not merely what one party habitually does.
Why the burden matters
Placing the burden of proof on the party asserting the custom prevents courts from applying vague or disputed norms as though they were settled law. If a custom were presumed to exist simply because someone claimed it, any party could invoke convenient local practices to escape contractual obligations or vary statutory rules. Article 12 closes that door by requiring the same evidentiary standard that applies to any other fact in dispute. If you cannot produce sufficient proof, the custom carries no legal weight in the proceeding — and the case is decided without it.
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.
- Metropolitan Fabrics, Inc., et al. vs Prosperity Credit Resources, Inc. et al, G.R. No. 154390, March 17, 2014 — read the decision on LawPhil →
- Monico San Diego vs. Eufrocinio Evangelista, G.R. No. 163680, January 24, 2006 — read the decision on LawPhil →
- Apolonia LL. Ocampo, et al. vs. Fidela LL. Ocampo, et al, G.R. No. 150707, April 14, 2004 — read the decision on LawPhil →