Both general insurance premiums and long-term care insurance premiums are calculated on a monthly basis. Employers are allowed to subtract only insurance premiums for the preceding month from insured persons' monthly salaries. This restriction was designed to help make sure that insured persons can support themselves.
Workers who acquire health insurance status in the middle of a month will have the full month's premium deducted from the next month's salary. Persons who lose their insurance status due to retirement and other reasons are exempt from payment of premiums for the month during which the status change takes place. Persons who retire from work or who die on the last day of a month must pay the premium for the following month, as the insurance status remains in effect until the first day of the following month.
A premium on a bonus is subtracted from the bonus itself.