The period of stay granted on a Certificate of Eligibility is determined based on the date of issuance.
The following rules apply:

• It must be longer than the remaining period of the sponsor’s granted period of stay.
• However, it cannot exceed more than one month beyond the sponsor’s granted period of stay.
• The period of stay is decided in full months (12 months are counted as one year).
• If the sponsor has not yet entered Japan, the dependent will be granted the same period of stay as the sponsor.

Example

• Date of issuance: September 2, 2025
• Sponsor’s granted period of stay until: January 14, 2026

From the issuance date to the sponsor’s expiration date is 4 months and 12 days.
According to the rule, the period of stay must be longer than this remaining period, so at least 5 months must be granted.

Counting 5 months from the issuance date gives February 2, 2026. Since this date is still within one month after the sponsor’s expiration (January 14, 2026), a period of stay of 5 months was granted.

At the time of the next renewal, you can apply for the renewal together with your sponsor.😊
As long as the sponsor is steadily employed and able to support the dependent, a one-year period of stay will be granted, so please rest assured.