Supplementary Provisions, Article 15
第十五条
With regard to the statutory interest rate relating to a claim that is to bear interest in the case where interest arose before the Effective Date, notwithstanding the provisions of Article 404 of the New Act, the provisions then in force continue to govern.
With regard to the application of the provisions of Article 404, paragraph (4) of the New Act to each term until the first change in the statutory interest rate pursuant to the provisions of that paragraph, the phrase "the most recent term during which there was a change in the statutory interest rate pursuant to the provisions of this paragraph (referred to as the 'most recent term of change' in this paragraph below)" in that paragraph is deemed to be replaced with "the first term after the enforcement of the Act for Partially Amending the Civil Code (Act No. 44 of 2017)", and the phrase "the statutory interest rate for the most recent term of change" is deemed to be replaced with "3% per annum".
新法第四百四条第四項の規定により法定利率に初めて変動があるまでの各期における同項の規定の適用については、同項中「この項の規定により法定利率に変動があった期のうち直近のもの（以下この項において「直近変動期」という。）」とあるのは「民法の一部を改正する法律（平成二十九年法律第四十四号）の施行後最初の期」と、「直近変動期における法定利率」とあるのは「年三パーセント」とする。