# 所得税法 / Income Tax Act — 第一条 (Supplementary Provisions, Article 1)

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- 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: 第一条 (Supplementary Provisions, Article 1)（施行期日） — address `suppl-5021-8/art-1`
- Text in force since: 2026-10-01
- URL (the page that opens at this provision): https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1
- 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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### 第一条（施行期日） — Effective Date
<sup>caption: machine translation, not official</sup>
<sup>suppl-5021-8/art-1 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1</sup>

**第一項**  この法律は、令和二年四月一日から施行する。ただし、次の各号に掲げる規定は、当該各号に定める日から施行する。
<sup>suppl-5021-8/art-1/par-1 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1</sup>
This Act comes into effect on April 1, 2020; provided, however, that the provisions set forth in the following items come into effect on the dates specified in those items:
<sup>machine translation, not official</sup>

  **一**  略
  <sup>suppl-5021-8/art-1/par-1/item-1 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-1</sup>
  Omitted
  <sup>machine translation, not official</sup>

  **二**  次に掲げる規定　令和三年一月一日
  <sup>suppl-5021-8/art-1/par-1/item-2 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-2</sup>
  the following provisions: January 1, 2021;
  <sup>machine translation, not official</sup>

    **イ**  第一条中所得税法第八十五条第二項の改正規定、同法第百八十七条の改正規定、同法第百九十四条第一項第二号の改正規定、同法第百九十五条第一項の改正規定（同項第四号に係る部分を除く。）、同法第二百三条の三第一号の改正規定、同法第二百三条の六第一項の改正規定（同項第六号に係る部分を除く。）、同法第二百二十一条に六項を加える改正規定並びに同法別表第二の備考（一）（４）、別表第三の備考（一）（４）及び別表第四の備考（二）の改正規定並びに附則第八条第一項及び第七項、第九条第一項及び第二項並びに第十条の規定
    <sup>suppl-5021-8/art-1/par-1/item-2/sub-1 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-2/sub-1</sup>
    the provision of Article 1 amending Article 85, paragraph (2) of the Income Tax Act, the provision amending Article 187 of that Act, the provision amending Article 194, paragraph (1), item (ii) of that Act, the provision amending Article 195, paragraph (1) of that Act (excluding the part concerning item (iv) of that paragraph), the provision amending Article 203-3, item (i) of that Act, the provision amending Article 203-6, paragraph (1) of that Act (excluding the part concerning item (vi) of that paragraph), the provision adding six paragraphs to Article 221 of that Act, and the provisions amending note (1)(4) to Appended Table 2, note (1)(4) to Appended Table III and note (2) to Appended Table 4 of that Act, and the provisions of Article 8, paragraphs (1) and (7), Article 9, paragraphs (1) and (2) and Article 10 of the Supplementary Provisions;
    <sup>machine translation, not official</sup>

  **三**  略
  <sup>suppl-5021-8/art-1/par-1/item-3 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-3</sup>
  Omitted
  <sup>machine translation, not official</sup>

  **四**  次に掲げる規定　令和四年一月一日
  <sup>suppl-5021-8/art-1/par-1/item-4 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-4</sup>
  the following provisions: January 1, 2022;
  <sup>machine translation, not official</sup>

    **イ**  第一条中所得税法第六十七条（見出しを含む。）の改正規定、同法第百二十条第四項第二号の改正規定、同条第六項の改正規定、同法第百六十六条の改正規定及び同法第二百三十二条の改正規定並びに附則第五条、第七条第二項及び第三項並びに第十一条の規定
    <sup>suppl-5021-8/art-1/par-1/item-4/sub-1 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-4/sub-1</sup>
    the provision of Article 1 amending Article 67 of the Income Tax Act (including its caption), the provision amending Article 120, paragraph (4), item (ii) of that Act, the provision amending paragraph (6) of that Article, the provision amending Article 166 of that Act and the provision amending Article 232 of that Act, and the provisions of Article 5, Article 7, paragraphs (2) and (3) and Article 11 of the Supplementary Provisions;
    <sup>machine translation, not official</sup>

  **五**  次に掲げる規定　令和四年四月一日
  <sup>suppl-5021-8/art-1/par-1/item-5 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-5</sup>
  the following provisions: April 1, 2022;
  <sup>machine translation, not official</sup>

    **イ**  第二条の規定及び附則第十三条の規定
    <sup>suppl-5021-8/art-1/par-1/item-5/sub-1 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-5/sub-1</sup>
    the provisions of Article 2 and the provisions of Article 13 of the Supplementary Provisions;
    <sup>machine translation, not official</sup>

  **六**  第一条中所得税法第二条第一項第三十四号の二の改正規定、同法第百二十条第三項の改正規定、同法第百九十四条の改正規定（同条第一項第二号に係る部分を除く。）、同法第百九十五条第一項第四号の改正規定、同条第四項の改正規定、同法第二百三条の六第一項第六号の改正規定及び同条第三項の改正規定並びに附則第三条、第七条第一項、第八条第八項及び第九条第三項の規定　令和五年一月一日
  <sup>suppl-5021-8/art-1/par-1/item-6 · https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-1/par-1/item-6</sup>
  the provision of Article 1 amending Article 2, paragraph (1), item (xxxiv)-2 of the Income Tax Act, the provision amending Article 120, paragraph (3) of that Act, the provision amending Article 194 of that Act (excluding the part concerning paragraph (1), item (ii) of that Article), the provision amending Article 195, paragraph (1), item (iv) of that Act, the provision amending paragraph (4) of that Article, the provision amending Article 203-6, paragraph (1), item (vi) of that Act and the provision amending paragraph (3) of that Article, and the provisions of Article 3, Article 7, paragraph (1), Article 8, paragraph (8) and Article 9, paragraph (3) of the Supplementary Provisions: January 1, 2023.
  <sup>machine translation, not official</sup>

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## Cites
- suppl-5021-8/art-1/par-1/item-2/sub-1: 附則第八条第一項 → 所得税法 附則第八条第一項 (Supplementary Provisions, Article 8, paragraph (1)), suppl-5021-8/art-8/par-1 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-8/par-1
- suppl-5021-8/art-1/par-1/item-2/sub-1: 第七項 → 所得税法 附則第八条第七項 (Supplementary Provisions, Article 8, paragraph (7)), suppl-5021-8/art-8/par-7 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-8/par-7
- suppl-5021-8/art-1/par-1/item-2/sub-1: 第九条第一項 → 所得税法 附則第九条第一項 (Supplementary Provisions, Article 9, paragraph (1)), suppl-5021-8/art-9/par-1 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-9/par-1
- suppl-5021-8/art-1/par-1/item-2/sub-1: 第二項 → 所得税法 附則第九条第二項 (Supplementary Provisions, Article 9, paragraph (2)), suppl-5021-8/art-9/par-2 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-9/par-2
- suppl-5021-8/art-1/par-1/item-2/sub-1: 第十条 → 所得税法 附則第十条 (Supplementary Provisions, Article 10), suppl-5021-8/art-10 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-10
- suppl-5021-8/art-1/par-1/item-4/sub-1: 附則第五条 → 所得税法 附則第五条 (Supplementary Provisions, Article 5), suppl-5021-8/art-5 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-5
- suppl-5021-8/art-1/par-1/item-4/sub-1: 第七条第二項 → 所得税法 附則第七条第二項 (Supplementary Provisions, Article 7, paragraph (2)), suppl-5021-8/art-7/par-2 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-7/par-2
- suppl-5021-8/art-1/par-1/item-4/sub-1: 第三項 → 所得税法 附則第七条第三項 (Supplementary Provisions, Article 7, paragraph (3)), suppl-5021-8/art-7/par-3 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-7/par-3
- suppl-5021-8/art-1/par-1/item-4/sub-1: 第十一条 → 所得税法 附則第十一条 (Supplementary Provisions, Article 11), suppl-5021-8/art-11 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-11
- suppl-5021-8/art-1/par-1/item-5/sub-1: 附則第十三条 → 所得税法 附則第十三条 (Supplementary Provisions, Article 13), suppl-5021-8/art-13 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-13
- suppl-5021-8/art-1/par-1/item-6: 附則第三条 → 所得税法 附則第三条 (Supplementary Provisions, Article 3), suppl-5021-8/art-3 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-3
- suppl-5021-8/art-1/par-1/item-6: 第七条第一項 → 所得税法 附則第七条第一項 (Supplementary Provisions, Article 7, paragraph (1)), suppl-5021-8/art-7/par-1 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-7/par-1
- suppl-5021-8/art-1/par-1/item-6: 第八条第八項 → 所得税法 附則第八条第八項 (Supplementary Provisions, Article 8, paragraph (8)), suppl-5021-8/art-8/par-8 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-8/par-8
- suppl-5021-8/art-1/par-1/item-6: 第九条第三項 → 所得税法 附則第九条第三項 (Supplementary Provisions, Article 9, paragraph (3)), suppl-5021-8/art-9/par-3 — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-9/par-3

## Cited by

1 provision cites this one. No official source publishes this direction.

- 所得税法 附則第百七十一条第一項（罰則に関する経過措置） — https://japanlaw.org/ja/income-tax-act/suppl-5021-8/art-171/par-1

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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-20260918T180319-128, 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