Consequences of Unpaid 国民年金 and 国民健康保険: Demand Letters, Late Charges, Exemptions and Residence Examinations

For people living in Japan, neither 国民年金 (こくみんねんきん, National Pension) nor 国民健康保険 (National Health Insurance) is a "voluntary" system. This article summarizes who must enroll, what happens if you cannot pay the premiums, what legitimate reductions and deferments are available, and what the official pages of 出入国在留管理庁 (Immigration Services Agency of Japan) say about payment status. It is intended as a self-check for international students, self-employed people, people who have just left their jobs, and people preparing to apply for permanent residency.

Key points

• People living in Japan who are aged 20 or older and under 60 and are not enrolled in 厚生年金保険 (Employees' Pension Insurance) are, in principle, all Category 1 or Category 3 insured persons of 国民年金, and the explanation by 日本年金機構 (Japan Pension Service) contains no nationality condition; the 国民年金保険料 (National Pension premium) for 令和8年度 (fiscal 2026) is 17,920 yen per month, and the payment deadline is the last day of the month following the month concerned.
• Foreign nationals with a period of stay of more than 3 months who are not enrolled in other medical insurance, such as company health insurance, must enroll in 国民健康保険; enrollment or withdrawal must be completed within 14 days at the counter of the 市区町村 (municipal office) where you live.
• A person who is able to pay 国民年金 premiums but does not pay for a long time will receive, in turn, a 「最終催告状」 (final demand notice) and a 「督促状」 (demand letter); if payment is still not made after the deadline set in the demand letter, property will be seized (差押え) and a late-payment charge (延滞金) will arise, and the 世帯主 (head of household) and spouse are also jointly liable for payment.
• If you are in financial difficulty, you can apply for 「免除」 (exemption), 「納付猶予」 (payment deferment) or 「学生納付特例」 (Special Payment System for Students), going back at most to 2 years and 1 month before the time of application; approved periods can be paid later through 「追納」 (retroactive payment) within 10 years.
• The 出入国在留管理庁 永住ガイドライン (permanent residency guidelines) state that payments not made within the original deadlines are, in principle, evaluated negatively, even if they have been paid by the time of application.

Who must enroll

国民年金

日本年金機構's page 「国民年金に加入するための手続き」 states that people living in Japan who are aged 20 or older and under 60 and are not enrolled in 厚生年金保険 all become Category 1 or Category 3 insured persons of 国民年金.

• Category 1 insured persons: self-employed people, students, people without work, etc. They pay the premiums themselves and enroll at the city or ward office (市区役所) or town or village office (町村役場) of their place of residence.
• Category 3 insured persons: people who are dependents of a spouse enrolled in 厚生年金, with an annual income of, in principle, less than 1.3 million yen, etc. The spouse's employer handles the procedure, and the person does not need to pay premiums themselves.

The procedure requires the 「国民年金被保険者関係届書（申出書）」 (notification form for National Pension insured persons) and documents that confirm the 基礎年金番号 (basic pension number) or マイナンバー (My Number (individual number)); if you do not have a マイナンバーカード (My Number Card), identity documents such as the 在留カード (residence card) are also required.

国民健康保険

厚生労働省 (Ministry of Health, Labour and Welfare) explains that people who have an address in Japan and do not fall under cases such as "already enrolled in other medical insurance (including as a dependent), receiving 生活保護 (public assistance), enrolled in the 後期高齢者医療制度 (Late-Stage Elderly Medical Care System), or foreign residents on 短期滞在 (Temporary Visitor)" become insured persons of 国民健康保険. 厚生労働省's leaflet for foreign nationals further states that foreign nationals with a period of stay of more than 3 months are subject to mandatory enrollment.

After withdrawing from company health insurance (for example, after leaving a job), you must also complete the 国民健康保険 enrollment procedure at the 市区町村 counter within 14 days. People from countries with a social security agreement sometimes do not need to enroll; whether you need to is to be confirmed at the 市区町村 counter.

What happens if 国民年金保険料 goes unpaid

Payment deadline and the 2-year limit

The payment deadline for premiums is set by law as the last day of the month following the month concerned (extended when it falls on a weekend, public holiday or the year-end and New Year holidays). 日本年金機構 explains that even after the payment deadline has passed, you can still pay with the payment slip (納付書) within 2 years of the deadline; portions older than 2 years can no longer be paid in the usual way.

The enforced collection process

According to 日本年金機構's page 「国民年金保険料の強制徴収」, the process is roughly as follows:

1. 納付勧奨 (payment reminders): if payment is not made by the deadline, staff of the organization or private contractors entrusted by it urge payment by phone or in writing.
2. 最終催告状: if a person is able to pay but still has not paid after repeated reminders, a final demand notice is sent.
3. 督促状: if payment is not made by the deadline set in the final demand notice, a demand letter is sent; if there are persons jointly liable for payment (head of household, spouse), it is also sent to them.
4. 差押え: if payment is not made by the deadline set in the demand letter, property is seized; the property of persons jointly liable for payment is also subject to seizure.

延滞金

The late-payment charge arises when premiums are paid after the deadline set in the demand letter. In the calculation, the period is divided into two parts, "within 3 months from the day after the deadline" and "after that", each multiplied by a different annual rate and calculated on a daily basis; after adding them up, amounts below 50 yen are rounded down, and a late-payment charge of less than 50 yen is not collected. The specific rates are published on 日本年金機構's page each year; refer to the official page.

If you cannot pay: 免除・納付猶予・学生納付特例

Not paying is different from an approved exemption or deferment: approved periods count toward the qualifying period required to receive a pension.

System	Main eligible persons	Scope of income screening
免除 (全額・4分の3・半額・4分の1) (exemption: full, three-quarters, half, one-quarter)	People who have difficulty paying, such as those whose previous year's income was at or below a certain amount	The person, spouse, head of household
納付猶予	Aged 20 or older and under 50	The person, spouse
学生納付特例	Students at universities, graduate schools, junior colleges, specialized training colleges, etc. (including evening and correspondence courses)	The person only

• The income threshold for full exemption and 納付猶予 is "(number of dependents, etc. + 1) × 350,000 yen + 320,000 yen" or less; for 学生納付特例 it is "1.28 million yen + 380,000 yen per dependent, etc. + social insurance premium deductions, etc." or less.
• In cases of unemployment, business failure, business closure and the like, you can sometimes apply under a special provision regardless of the previous year's income.
• The periods you can apply for are those less than 2 years from the payment deadline, going back at most to 2 years and 1 month before the time of application. 学生納付特例 is, in principle, screened for each year from April to March of the following year, and you need to apply every year.

Effect on pension amount and 追納

• Periods of full exemption are counted as 1/2 of the pension amount for full payment (1/3 for months up to March 平成21 (2009)), and partial exemptions are reflected proportionally.
• Periods of 納付猶予 and 学生納付特例 count toward the qualifying period but are not reflected in the pension amount.
• Approved periods can be paid retroactively (追納) within 10 years; if you pay in or after the third fiscal year following the approved period, a certain amount is added (日本年金機構's page notes that there is no additional amount for months in fiscal 2024 (令和6年度) and fiscal 2025 (令和7年度)). People who are already eligible to receive the 老齢基礎年金 (Old-age Basic Pension) cannot make retroactive payments.

Unpaid 国民健康保険料（税）

国民健康保険 premiums are called 「保険料」 (insurance premium) in some places and 「保険税」 (insurance tax) in others. The specific calculation method, payment deadlines and payment methods are set by each municipality's ordinance, and premiums are calculated per household (世帯). 厚生労働省 explains the following nationwide measures:

• For households with income below the statutory threshold, the 均等割・平等割 (per-capita and per-household) portions can be reduced by 70%, 50% or 20%.
• For people who lost their jobs involuntarily because of bankruptcy, dismissal and the like, the previous year's salary income is calculated at 30/100 from the time of job loss until the end of the following fiscal year.
• People who have difficulty paying because of special circumstances such as disasters may be granted a reduction, exemption or deferment; consult the 国保 (National Health Insurance) counter of your municipality.

厚生労働省's leaflet for foreign nationals states that if you do not pay for a long time, the following may happen:

• Your property may be seized;
• Benefits may be restricted, so that you must first pay the full amount at the medical institution's counter when seeing a doctor and then apply for reimbursement once conditions are met;
• Your payment status for premiums (tax) may be used as a factor in decisions on extension of period of stay, change of status of residence, and so on.

If you are in financial difficulty, you may be able to use systems such as reductions or installment payments, so consult the 市区町村 counter as early as possible. For specific handling of demand letters, late-payment charges and so on, refer to the explanation of each 市区町村.

Effect on residence examinations

The following only summarizes what is stated on the official pages of 出入国在留管理庁:

• Permanent residency: the 「永住許可に関するガイドライン（令和８年２月２４日改訂）」 (Guidelines for Permission for Permanent Residence, revised February 24, 2026) lists "properly fulfilling public obligations (paying taxes, paying public pension and public medical insurance premiums, and the notification obligations under the Immigration Control Act, etc.)" as one of the requirements, and notes that even if payments have been completed by the time of application, obligations not fulfilled within the original payment periods are, in principle, evaluated negatively.
• 在留期間更新・在留資格変更 (extension of period of stay and change of status of residence): item 7 of the 「在留資格の変更、在留期間の更新許可のガイドライン」 (Guidelines for Change of Status of Residence and Extension of Period of Stay) (last revised June 令和8 (2026)) states that where non-payment of 国民健康保険料 or other amounts payable under law is found to be large or long-term and malicious, it is evaluated as a negative factor in the same way as non-fulfillment of tax obligations; the Immigration Services Agency may make its decision based on information about payment status obtained from the relevant agencies.
• The same guidelines explain that at the time of application the counter will ask you to show the 「資格情報」 (eligibility information) screen on マイナポータル (Mynaportal), the 「資格情報のお知らせ」 (notice of eligibility information) or the 「資格確認書」 (eligibility certificate), but an application will not be refused solely because you cannot show them.

Individual cases depend on the immigration examination.

Timeline

1. After arriving in Japan, turning 20 or leaving a company: enroll in 国民健康保険 within 14 days; at the same time, complete the procedure as a Category 1 insured person of 国民年金 at the 市区町村 counter.
2. Every month: pay the month's premium by the last day of the following month.
3. When your income falls or you become a student: apply for 免除・納付猶予・学生納付特例 as early as possible (it can go back to 2 years and 1 month before the time of application).
4. Within 2 years of the payment deadline: unpaid 国民年金 premiums can still be paid.
5. Within 10 years after an exemption etc. is approved: you can make retroactive payments (追納); from the third fiscal year, an additional amount may apply.
6. Before applying for permanent residency or an extension: check whether every installment was paid by its deadline.

Common misconceptions

• "Foreign nationals don't have to enroll in 国民年金." 日本年金機構's explanation of who must enroll contains no nationality condition; in principle, everyone living in Japan who is aged 20 or older and under 60 and not enrolled in 厚生年金 must enroll.
• "Paying everything at once later will be fine." The 永住ガイドライン state clearly that payments not made by the original deadlines are, in principle, evaluated negatively even if paid by the time of application; also, 国民年金 premiums more than 2 years old cannot be paid in the usual way.
• "学生納付特例 means you don't have to pay." It is only a deferment; the period is not reflected in the pension amount, and to increase your pension you need to make retroactive payments (追納) within 10 years.
• "If I can't pay, I'll just leave it." Leaving it leads to demand letters, late-payment charges and seizure; you should apply for 免除・猶予, and for 国民健康保険, consult the 市区町村 about reductions or installments.