If a period has been fixed by the day, week, month or year, the period shall mature upon the expiration of the last day of such period.
Civil Act — Article 159 (Maturity point of period)
민법 제159조
For AI agents and developers — get this article as JSON, with the English and current Korean effective dates and an outdated-translation flag, from the korea-law API or as an MCP tool:
https://mcp.apify.com?tools=kr-data/korea-law