If paragraph (1) of the preceding Article applies, the calculation of the tax prepayment calculation base is based on what has been established as of May 15 of the relevant year, and the determination as to whether a person falls under the category of a Resident is based on the person's circumstances as of June 30 of the relevant year; provided, however, that if the amount calculated based on what has been established as of any date between May 16 and July 31 of the relevant year turns out to be less than the amount calculated pursuant to the provisions of the main clause, the calculation of the tax prepayment calculation base is based on what has been established as of that date (or as of the day on which the amount so calculated is the smallest, if there are two or more such dates).
Read this with the articles around it
Resident
「居住者」
An individual who has a domicile in Japan, or who has had a residence in Japan continuously for one year or more up to now.
Defined inArticle 2, paragraph (1), item (iii)· applies throughout the law
tax prepayment calculation base
「予定納税基準額」
The base amount for a resident's income tax prepayments (予定納税): broadly the previous year's income tax on regular income, less the tax withheld at source on that income; when it is 150,000 yen or more, a third of it must be paid in July and another third in November.
Short name set inArticle 104, paragraph (1)· applies only in this chapter