# Act No. 12 of 2026: Act Partially Amending the Income Tax Act, etc.

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Every law on japanlaw.org that Act No. 12 of 2026 amends, and when each change takes effect; promulgated 31 March 2026.

- Number: 令和八年法律第十二号 (令和8年法律第12号), Act No. 12 of 2026
- Title: Act Partially Amending the Income Tax Act, etc. (所得税法等の一部を改正する法律)
- Promulgated: 31 March 2026
- In Japanese: https://japanlaw.org/ja/acts/508AC0000000012
- Changes to Japanese law, by date: https://japanlaw.org/en/changes (as Markdown: https://japanlaw.org/md/en/changes)

## Consumption Tax Act (消費税法)

https://japanlaw.org/en/consumption-tax-act

- 1 April 2026: Since replaced.
- 1 April 2027: Not yet in force. 4 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/consumption-tax-act/amendments/20270401_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/consumption-tax-act/amendments/20270401_508AC0000000012/text
- 1 October 2027: Not yet in force. 4 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/consumption-tax-act/amendments/20271001_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/consumption-tax-act/amendments/20271001_508AC0000000012/text
- 1 April 2028: Not yet in force. 35 provisions changed · 86 provisions added · 13 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/consumption-tax-act/amendments/20280401_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/consumption-tax-act/amendments/20280401_508AC0000000012/text

## Corporation Tax Act (法人税法)

https://japanlaw.org/en/corporation-tax-act

- 1 April 2026: Since replaced.
- 1 October 2026: In force. The law in force: https://japanlaw.org/en/corporation-tax-act; in Markdown: https://japanlaw.org/md/en/corporation-tax-act
- 1 January 2027: Not yet in force. 1 provision in the supplementary provisions. What it changes: https://japanlaw.org/en/corporation-tax-act/amendments/20270101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/corporation-tax-act/amendments/20270101_508AC0000000012/text

## Income Tax Act (所得税法)

https://japanlaw.org/en/income-tax-act

- 1 April 2026: Since replaced.
- 1 December 2026: Not yet in force. 6 provisions changed · 1 provision removed · 14 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/income-tax-act/amendments/20261201_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/income-tax-act/amendments/20261201_508AC0000000012/text
- 1 January 2027: Not yet in force. 10 provisions changed · 1 provision added · 5 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/income-tax-act/amendments/20270101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/income-tax-act/amendments/20270101_508AC0000000012/text
- Date not yet set: Not yet in force. 4 provisions changed · 1 provision in the supplementary provisions. What it changes: https://japanlaw.org/en/income-tax-act/amendments/20270722_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/income-tax-act/amendments/20270722_508AC0000000012/text
- Date not yet set: Not yet in force. 9 provisions changed · 3 provisions added · 3 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/income-tax-act/amendments/20280101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/income-tax-act/amendments/20280101_508AC0000000012/text

## Act on the Use of Numbers to Identify a Specific Individual in Administrative Procedures (行政手続における特定の個人を識別するための番号の利用等に関する法律)

https://japanlaw.org/en/my-number-act

- 1 April 2026: Since replaced.
- 1 January 2027: Not yet in force. 1 provision changed. What it changes: https://japanlaw.org/en/my-number-act/amendments/20270101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/my-number-act/amendments/20270101_508AC0000000012/text

## Act on General Rules for National Taxes (国税通則法)

https://japanlaw.org/en/national-tax-general-rules-act

- 1 April 2026: Since replaced.
- 1 October 2027: Not yet in force. 44 provisions changed · 51 provisions added · 2 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/national-tax-general-rules-act/amendments/20271001_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/national-tax-general-rules-act/amendments/20271001_508AC0000000012/text
- 1 April 2028: Not yet in force. 1 provision changed · 1 provision added. What it changes: https://japanlaw.org/en/national-tax-general-rules-act/amendments/20280401_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/national-tax-general-rules-act/amendments/20280401_508AC0000000012/text

## Act on Special Measures for Securing the Financial Resources Necessary to Implement Measures for Reconstruction following the Great East Japan Earthquake (東日本大震災からの復興のための施策を実施するために必要な財源の確保に関する特別措置法)

https://japanlaw.org/en/reconstruction-funding-act

- 1 April 2026: In force. The law in force: https://japanlaw.org/en/reconstruction-funding-act; in Markdown: https://japanlaw.org/md/en/reconstruction-funding-act
- 1 December 2026: Not yet in force. 1 provision in the supplementary provisions. What it changes: https://japanlaw.org/en/reconstruction-funding-act/amendments/20261201_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/reconstruction-funding-act/amendments/20261201_508AC0000000012/text
- 1 January 2027: Not yet in force. 52 provisions changed · 4 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/reconstruction-funding-act/amendments/20270101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/reconstruction-funding-act/amendments/20270101_508AC0000000012/text
- Date not yet set: Not yet in force. 1 provision changed. What it changes: https://japanlaw.org/en/reconstruction-funding-act/amendments/20280101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/reconstruction-funding-act/amendments/20280101_508AC0000000012/text

## Act on Special Measures Concerning Taxation (租税特別措置法)

https://japanlaw.org/en/special-taxation-measures-act

- 1 April 2026: Since replaced.
- 1 May 2026: Since replaced.
- 25 June 2026: Since replaced.
- 31 July 2026: Since replaced.
- 1 October 2026: Since replaced.
- Date not yet set: Not yet in force. 2 provisions changed. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20261126_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20261126_508AC0000000012/text
- 1 December 2026: Not yet in force. 7 provisions changed · 10 provisions added · 2 provisions removed · 6 provisions in the supplementary provisions · 1 article renumbered. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20261201_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20261201_508AC0000000012/text
- Date not yet set: Not yet in force. 10 provisions changed · 2 provisions added. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20261204_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20261204_508AC0000000012/text
- 1 January 2027: Not yet in force. 92 provisions changed · 57 provisions added · 6 provisions removed · 11 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20270101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20270101_508AC0000000012/text
- 20 May 2027: Not yet in force. 1 provision changed. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20270520_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20270520_508AC0000000012/text
- Date not yet set: Not yet in force. 7 provisions changed. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20270526_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20270526_508AC0000000012/text
- Date not yet set: Not yet in force. 4 provisions changed · 35 provisions added. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20270618_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20270618_508AC0000000012/text
- Date not yet set: Not yet in force. 35 provisions changed · 26 provisions added · 6 provisions in the supplementary provisions. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20280101_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20280101_508AC0000000012/text
- 1 April 2028: Not yet in force. 1 provision changed. What it changes: https://japanlaw.org/en/special-taxation-measures-act/amendments/20280401_508AC0000000012; the law as amended, in Markdown: https://japanlaw.org/md/en/special-taxation-measures-act/amendments/20280401_508AC0000000012/text

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## Sources

- The dates and the amending law: e-Gov (Digital Agency) (7 records)
- English title of the amending law: Written for this site with AI
- English names of the laws: Japanese Law Translation, Ministry of Justice (6 records)
- English names of the laws: Written for this site with AI