Text of the provision
Art. 13. When the laws speak of years, months, days or nights, it shall be understood that years are of three hundred sixty-five days each; months, of thirty days; days, of twenty-four hours; and nights from sunset to sunrise.
If months are designated by their name, they shall be computed by the number of days which they respectively have. In computing a period, the first day shall be excluded, and the last day included.
(7a)
Civil Code of the Philippines, Republic Act No. 386, approved June 18, 1949, effective August 30, 1950. Reproduced in full; verified verbatim against the LawPhil and ChanRobles official-text renderings. Note: for reckoning periods, the Administrative Code of 1987 (Sec. 31, Chap. 8, Book I) now provides that a year means twelve calendar months, which the Supreme Court has applied over this article's 365-day rule (CIR v. Primetown, 2007).
What this article means
This supplies the default arithmetic for legal periods: a year = 365 days, a month = 30 days, a day = 24 hours, and a night runs from sunset to sunrise. Named months are counted by their actual length. In counting a period, you exclude the first day and include the last. Note a modern wrinkle: for computing a year, the Supreme Court in CIR v. Primetown applied the Administrative Code's rule of twelve calendar months instead of 365 days.
Related provisions
- Article 14 — territorial reach of penal laws.
- Article 2 — the 15-day period for laws to take effect.
Cases interpreting this article
- Authorities on this article will be added here as each is verified against primary sources.