①A category 1 insured person (excluding a person who is not required to pay a premium under Article 89, paragraph (1), Article 90, paragraph (1), or Article 90-3, paragraph (1), a person who is not required to pay part of the amount of a premium under Article 90-2, paragraphs (1) through (3), and a member of a National Pension Fund) may, by notifying the Minister of Health, Labour and Welfare, become a person who pays a premium of 400 yen, in addition to the premium in the amount specified in paragraph (3) of the preceding Article, for each month on and after the month that contains the day on which that notification was made.

②Payment of a premium under the preceding paragraph may be made only for a month in which the premium in the amount specified in paragraph (3) of the preceding Article was paid (excluding a month in which the premium is deemed to have been paid under Article 94, paragraph (4)), or for each month in the period relating to a premium not required to be paid under Article 88-2.

③A person who has become a person who pays a premium under paragraph (1) may, at any time, by notifying the Minister of Health, Labour and Welfare, cease to be a person who pays a premium under paragraph (1), with respect to the premium for each month on and after the month preceding the month that contains the day on which that notification was made (excluding a premium already paid, and a premium prepaid under Article 93, paragraph (1) (excluding one relating to each month on and after the month that contains the day on which the person became a member of a National Pension Fund)).

④When a person who has become a person who pays a premium under paragraph (1) becomes a member of a National Pension Fund, that person is deemed to have made the request under the preceding paragraph on the day on which the person became a member.