NTA corporate-number structure — selected English translation

Source: National Tax Agency, About corporate numbers (法人番号について), July 2023, printed page 2 / PDF page 5: Japanese PDF. Read 2026-09-17. Selected translation of the structure text and table, not the whole booklet. The source PDF is retained outside Git in /data/brific/japan_mic/2026-09-17-fx-screen/nta-corporate-numbers.pdf.

A corporate number has 13 digits: a 12-digit base number preceded by a one-digit check digit. For an incorporated entity registered under the commercial registration system, the base is its 12-digit company/corporation registration number. For other entities, the assigned base differs from every other corporate number's base and every company/corporation registration number.

Entity category Base-number structure, excluding the leading check digit
National legislative body 000011 + six-digit serial number
National administrative body 000012 + six-digit serial number
National judicial body 000013 + six-digit serial number
Local public body 000020 or 000030 + six-digit serial number
Registered corporation Four-digit registry-office code + two-digit organization category + six-digit serial number
Unregistered corporation or association without legal personality Begins with 7, followed by serial-number digits

The table marks bases beginning with 6, 8 and 9 as unused, and shows registered-corporation registry-office codes from 0100 through 5000.

The NTA structure FAQ also states that an assigned corporate number cannot be changed.

Research interpretation: these fields describe registration and entity category, not industry. The local-public-body prefix is broader than municipalities.