# Changes to Japanese law on 18 December 2025

This is the Markdown twin of https://japanlaw.org/en/changes/2025-12-18. Every law, and how to address a provision: https://japanlaw.org/llms.txt. The same laws as MCP tools (no sign-in): https://japanlaw.org/mcp.

What changed on 18 December 2025 in 2 laws on this site: for each, the Act that amends it.

- Income Tax Act (所得税法) — https://japanlaw.org/en/income-tax-act
  - Amended by Act Partially Amending the Income Tax Act, etc. (Act No. 13 of 2025) (所得税法等の一部を改正する法律)
    The Act, and every law here it amends: https://japanlaw.org/en/acts/507AC0000000013 (as Markdown: https://japanlaw.org/md/en/acts/507AC0000000013)
    Listed with the law's amendments: https://japanlaw.org/en/income-tax-act/amendments; the text on e-Gov: https://laws.e-gov.go.jp/law/340AC0000000033/20251218_507AC0000000013
- Corporation Tax Act (法人税法) — https://japanlaw.org/en/corporation-tax-act
  - Amended by Act Partially Amending the Income Tax Act, etc. (Act No. 13 of 2025) (所得税法等の一部を改正する法律)
    The Act, and every law here it amends: https://japanlaw.org/en/acts/507AC0000000013 (as Markdown: https://japanlaw.org/md/en/acts/507AC0000000013)
    Listed with the law's amendments: https://japanlaw.org/en/corporation-tax-act/amendments; the text on e-Gov: https://laws.e-gov.go.jp/law/340AC0000000034/20251218_507AC0000000013

Every day: https://japanlaw.org/en/changes

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## Sources

- Amendments and their dates: e-Gov (Digital Agency) (2 records)
- English names of the laws: Japanese Law Translation, Ministry of Justice (2 records)
- English titles of the amending laws: Written for this site with AI