Naturalization Requirements Extended to 10 Years｜New Standards Effective April 1, 2026 (5 Years of Tax Records Required) Explained by an Immigration Lawyer

1. How will naturalization requirements change from April 1, 2026?

On March 27, 2026, the Ministry of Justice announced that new screening standards for foreign national naturalization applications will be applied to decisions made on or after April 1, 2026.

The two major changes are as follows:

• Residence requirement: 5 years → 10 years
• Tax certificates: 1 year → 5 years

These changes are not amendments to the Nationality Act, but rather revisions to administrative screening practice. However, the practical impact is expected to be very significant.

2. Basic Naturalization Requirements (Screening Standards After April 1, 2026)

In order for a foreign national to obtain Japanese nationality, it is necessary to satisfy several requirements based on Article 5 of the Nationality Act of Japan.

Typical requirements include the following:

• Having a residence history in Japan for 10 years or more (change in screening practice)
• Maintaining good conduct
• Having a stable livelihood and financial foundation
• Demonstrating willingness to comply with the Constitution of Japan

Among these requirements, the residence requirement was previously understood as “5 years or more,” however, for applications reviewed after April 1, 2026, the screening practice has changed to place emphasis on a residence history of approximately 10 years or more.

3. Tax Certificates Requirement Expanded to 5 Years

The scope of tax payment records reviewed during naturalization screening has also changed as of April 1, 2026.

Previously, confirmation mainly focused on tax certificates for the most recent year. However, the screening practice has now changed to confirm tax payment records for the past five years.

The main items subject to confirmation include the following:

• Resident tax
• Income tax
• National Health Insurance premiums
• National Pension contributions

Therefore, if there are any unpaid taxes or installment payment histories in the past, these may affect the outcome of naturalization screening.

4. Social Insurance Confirmation Period Expanded to 2 Years

For naturalization screening conducted after April 1, 2026, the confirmation period for social insurance payment status has also been extended.

Previously, screening mainly focused on payment records for the most recent year, however, payment status for the most recent two years is now subject to review.

• Health insurance
• Employees’ pension insurance
• National pension
• National Health Insurance

As a result, if there were any periods of non-enrollment or unpaid insurance premiums in the past, these may affect naturalization screening.

5. Why Were Naturalization Requirements Revised to 10 Years?

This change in screening practice is based on the policy framework titled “Comprehensive Measures for Foreign Resident Policy” announced by the Japanese government in January 2026.

The background includes the following policy objectives:

• Ensuring consistency with permanent residence requirements (generally 10 years)
• Maintaining the credibility of the nationality acquisition system
• Strengthening verification of stable living foundations in Japan

Because naturalization is a system for acquiring Japanese nationality, it is considered necessary to confirm a longer-term record of residence and stability in Japan.

6. How Will Naturalization Requirements for Spouses of Japanese Nationals Change?

For spouses of Japanese nationals, there is a system known as “simplified naturalization” under Article 6 of the Nationality Act.

Under this system, it has traditionally been possible to apply for naturalization if the applicant satisfies the following:

• Married for 3 years or more
• Resided in Japan for 1 year or more

The operational change introduced on April 1, 2026, is not an amendment to the Nationality Act itself, but rather a revision of screening practice.

Therefore, it is generally understood that the simplified naturalization provisions applicable to spouses of Japanese nationals and similar cases will remain in place.

However, the stricter review of tax payment status and social insurance enrollment/payment records may also affect simplified naturalization applications.

7. Who Will Be Affected by This Policy Change?

Due to this change in screening practice, it may become necessary to allow a longer preparation period for naturalization applications than before.

The following cases are especially likely to be affected:

• Those who have lived in Japan for more than 5 years but less than 10 years
• Those who have changed jobs frequently
• Those who have unpaid tax records within the past 5 years
• Those who have gaps in their social insurance enrollment history

Even for people who would previously have been considered eligible to apply for naturalization, the new standards may require a review of the timing of their application.

8. Impact on Those Who Have Already Applied for Naturalization

The new standards will apply to cases in which the permission decision is made on or after April 1, 2026.

Therefore,

• applications that have already been filed
• applications currently under review
• applications awaiting results

may also become subject to the new standards.

In particular, if the applicant’s period of residence is less than 10 years, there may be cases in which additional documents must be submitted or withdrawal of the application needs to be considered.

9. How Will the Difference Between Naturalization and Permanent Residency Change?

As a result of this operational change, the residence requirement for naturalization has become closer to the general requirement for permanent residency, namely “10 years or more of residence history in Japan.”

Therefore,

• whether to aim for naturalization
• or whether to aim for permanent residency

will require more careful consideration than before.

Naturalization vs. Permanent Residency in Japan｜2026 Updated Comparison Guide

ACROSEED Immigration Lawyer's Office provides a detailed explanation of the advantages and disadvantages of naturalization and permanent residency, as well as differences in eligibility requirements and screening standards.

10. Impact on Companies｜How Will Naturalization Strategies for Foreign Employees Change?

The changes to naturalization screening standards effective April 1, 2026 will also have a significant impact on corporate HR strategies for companies employing foreign nationals.

Until now, naturalization applications have often been positioned as a milestone for long-term employee retention. However, due to the recent change in screening practice, the timing of naturalization eligibility may be substantially delayed.

① The Timeline to Naturalization Will Become Longer

Previously, it was generally possible to apply for naturalization after approximately five years of residence in Japan. However, under current screening practice, a residence history of about 10 years or more is now required in practice.

As a result, companies need to more strategically consider:

• medium- to long-term employment planning assuming future naturalization
• roadmaps for employee retention
• prioritization between permanent residency applications and naturalization

more carefully than before.

② More Cases Will Prioritize Permanent Residency Applications First

Because the residence requirement for naturalization has become similar to the general requirement for permanent residency (typically 10 years), the importance of choosing between

• pursuing naturalization
• or pursuing permanent residency

has increased for foreign employees.

In particular, from a corporate HR perspective,

• greater flexibility in internal transfers
• reduced administrative burden related to visa expiration management
• stabilization of personnel systems

may lead to an increase in cases where permanent residency is prioritized.

③ The Importance of Tax and Social Insurance Compliance Management Will Increase

Under the new screening practice,

• tax payment records: confirmed for 5 years
• social insurance payments: confirmed for 2 years

and the confirmation period has been extended.

Therefore, companies are increasingly expected to ensure:

• proper enrollment in social insurance
• transparency in salary structure
• appropriate tax compliance management

to support future naturalization eligibility.

④ Impact on Retention Strategies for Highly Skilled Foreign Professionals

Naturalization has traditionally been one of the key options supporting long-term retention of highly skilled foreign professionals.

However, due to the recent change in screening practice,

• the timeline to naturalization has become longer
• the relationship between naturalization and permanent residency options has changed
• career planning implications have increased

These changes may affect long-term workforce strategy.

Companies should therefore consider not only employee preferences, but also long-term residence status strategy as a whole.

⑤ Companies May Need to Review Their Naturalization Support Systems

Previously, naturalization applications were often handled primarily by employees themselves. However, under the revised screening practice, corporate support systems are becoming increasingly important.

• assistance with organizing tax payment history
• verification of social insurance enrollment records
• review of residence status change history

Proper management of these elements by the company can help increase the likelihood of successful naturalization applications in the future.

11. Summary of the Stricter Naturalization Requirements

This change in screening practice represents a major turning point in the practical operation of Japan’s naturalization system.

In particular, because the confirmation period for tax payment records has been extended to five years, organizing past social insurance enrollment status and tax compliance history has become more important than ever.

If you are considering applying for naturalization, it is important to begin preparation early, based on your current residence history and tax payment records.

Sources and Primary References

• Ministry of Justice (Japan) Nationality Act (Act No.147 of 1950), Articles 5 and 6
  Legal provisions establishing the fundamental requirements for naturalization permission
• Government of Japan Office for the Promotion of an Orderly Society of Coexistence with Foreign Nationals “Basic Policy Toward Realizing an Orderly Society of Coexistence with Foreign Nationals” (Published January 2026)
  Policy document outlining strengthened operation of permanent residency and naturalization systems
• Ministry of Justice “Discussion Points for Reviewing the Basic Approach to the Acceptance of Foreign Nationals” (Interim Report of the Minister of Justice Private Study Group, August 13, 2025)
  Policy material indicating the need to strengthen reliability of permanent residency and naturalization systems
• Kyodo News Report “Government Considering Stricter Naturalization Requirements Including Extension of Residence Requirement Beyond Five Years” (November 25, 2025)
• Kyodo News Report “Government Considering Stricter Naturalization Requirements Including Extension of Residence Requirement Beyond Five Years” (November 26, 2025)
• Ministry of Justice Civil Affairs Bureau “Trends in the Number of Naturalization Applications” “Number of Naturalization Approvals by Nationality” Statistical data regarding application numbers and approval rates
• Operational explanations and consultation responses from Local Legal Affairs Bureau Nationality Divisions regarding practical screening changes effective April 1, 2026

This page has been prepared and explained from a practical professional perspective by ACROSEED Immigration Lawyer's Office based on publicly available materials, statistics, and media reports listed above.
Specific operational standards and numerical thresholds related to naturalization screening may be revised in the future depending on government policy developments and official guidelines. Please confirm with the latest primary sources when preparing your application.

12. Related Pages on Naturalization and Permanent Residency

Japan Naturalization Application Guide

Experts explain in detail the requirements for naturalization, the step-by-step application process, and the necessary documents.

Japan Permanent Residency Application Guide

A comprehensive overview of permanent residency applications in Japan. We thoroughly explain the key requirements (income, years of stay, tax/pension compliance), typical patterns by status of residence, and what to do if your application is denied.

Naturalization vs. Permanent Residency in Japan｜2026 Updated Comparison Guide

ACROSEED Immigration Lawyer's Office provides a detailed explanation of the advantages and disadvantages of naturalization and permanent residency, as well as differences in eligibility requirements and screening standards.

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