The background requirements include payment of taxes, pension and health insurance, and a criminal record. With regard to taxes (income tax, resident tax, etc.), it is important that you have paid all your taxes to date. If you have not paid them, you must pay them all.
Pension
Pensions have become a very important point of examination in recent years. As of March 2021, the past two years' worth of pension payments are being considered. Foreigners who are enrolled in an employee's pension plan at their company have no problem at all, but unexpectedly many foreigners who are not enrolled in an employee's pension plan do not fulfill their obligation to pay the National Pension Plan. The National Pension is not deducted from their monthly income, but they are required to pay it themselves, but we often hear that they were unaware of this fact.
The payment slip sent from the pension office has a due date. It is not enough to just make all the payments, but it is also important to pay by the due date. Therefore, even if you pay for a year at a time, it will not be effective in the examination for permanent residence because you have not paid.
Health insurance
Furthermore, there is health insurance. If you have health insurance through your company, there is no problem, but if you do not have health insurance through your company, you will be covered by the National Health Insurance of your local municipality. National Health Insurance also has a payment due date on the payment slip, so it is necessary that the payment is made on time.
The way they examine the payment is by asking you to submit receipts. Please note that National Health Insurance, like pensions, is often denied for failure to pay by the due date.
