# 所得税法 / Income Tax Act — 附　則 (Supplementary Provisions)

This is the Markdown twin of https://japanlaw.org/en/income-tax-act/suppl-4231-93. 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.

- Law: 所得税法 (Income Tax Act), 昭和四十年法律第三十三号
- English title "Income Tax Act": Ministry of Justice translation
- Kind: Act — the distinction between 法律 (Act), 政令 (Cabinet Order), 省令 (Ministerial Order) and 条例 (local ordinance) decides who may issue it and what it may say.
- Provision: 附　則 (Supplementary Provisions) — address `suppl-4231-93`
- Text in force since: 2026-10-01
- URL (the page that opens at this provision): https://japanlaw.org/en/income-tax-act/suppl-4231-93
- e-Gov law ID: 340AC0000000033 — never renamed. A permanent link, `/l/{lawId}/{address}` on this site, redirects to the page.
- Every provision below carries its address and its URL on the line under it.
- Japanese text: e-Gov 法令検索, Digital Agency (デジタル庁). English: as marked on each line below.

Only the Japanese as published by the government has legal effect; the text
below is a copy of it. Every English rendering below is a translation and
says which kind: the Ministry of Justice's translation, or this
site's machine translation, whose model and date the Sources list names.
They are never merged and never substituted for one another.

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## 附　則 平成二三年八月一〇日法律第九三号
<sup>suppl-4231-93 · https://japanlaw.org/en/income-tax-act/suppl-4231-93</sup>

### 第一条（施行期日） — Effective Date
<sup>caption: machine translation, not official</sup>
<sup>suppl-4231-93/art-1 · https://japanlaw.org/en/income-tax-act/suppl-4231-93/art-1</sup>

**第一項**  この法律は、公布の日から施行する。ただし、次の各号に掲げる規定は、それぞれ当該各号に定める日から施行する。
<sup>suppl-4231-93/art-1/par-1 · https://japanlaw.org/en/income-tax-act/suppl-4231-93/art-1/par-1</sup>
This Act comes into effect on the date of promulgation; provided, however, that the provisions set forth in the following items come into effect on the dates specified respectively in those items:
<sup>machine translation, not official</sup>

  **一**  第四条中確定拠出年金法目次の改正規定（「第二十一条」を「第二十一条の三」に改める部分に限る。）、同法第三条第三項第七号の次に一号を加える改正規定、同法第四条第一項第三号の次に一号を加える改正規定、同法第十九条及び第二十条の改正規定並びに同法第二章第三節中第二十一条の次に二条を加える改正規定並びに附則第八条の規定　平成二十四年一月一日
  <sup>suppl-4231-93/art-1/par-1/item-1 · https://japanlaw.org/en/income-tax-act/suppl-4231-93/art-1/par-1/item-1</sup>
  the provisions in Article 4 amending the table of contents of the Defined Contribution Pension Act (limited to the part replacing "Article 21" with "Article 21-3"), adding one item after Article 3, paragraph (3), item (vii) of that Act, adding one item after Article 4, paragraph (1), item (iii) of that Act, amending Articles 19 and 20 of that Act, and adding two Articles after Article 21 in Chapter II, Section 3 of that Act, and the provisions of Article 8 of the Supplementary Provisions: January 1, 2012.
  <sup>machine translation, not official</sup>

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## Sources

- e-Gov 法令検索, Digital Agency (デジタル庁) — 所得税法 — the text in force from 2026-10-01 (https://laws.e-gov.go.jp/law/340AC0000000033/20261001_507AC0000000070), retrieved 2026-10-05
- Japanese Law Translation Database System, Ministry of Justice (法務省) — Income Tax Act — Ministry of Justice translation (https://www.japaneselawtranslation.go.jp/en/laws/view/3120/tb), retrieved 2026-09-18
- claude-opus-5[1m] — Machine translation, batch income-tax-act-20260918T180319-111, translated 2026-09-18
- This site's parser, version 224 — 所得税法 — structure, counts, cross-references and defined terms, computed 2026-10-05