Japan
CoinPost
Asking the National Tax Agency about the next-generation "KSK2" system and tax audits of crypto assets
- The old KSK system, built around paper-based workflows (e.g., printing input data on forms for verification), limited data integration and made cross-category data analysis cumbersome; KSK2 unifies the databases while carefully managing access permissions, enabling integrated search across a taxpayer's income tax and asset tax records to support fairer, more accurate tax administration.
- Crypto assets span multiple tax categories (trading gains fall under income tax, while gifts and inheritance fall under asset-related taxes), so the NTA says cross-category data access is especially relevant to how such assets are taxed.
- In FY2024 (Reiwa 6, July 2024–June 2025), the average additional tax assessed per on-site audit of individuals trading crypto assets was JPY 7.45 million, 2.5 times the JPY 2.99 million average across all in-depth income tax field audits (613 crypto-related cases vs. 36,404 cases overall); the NTA attributes the gap partly to crypto's high price volatility, which can produce large gains depending on transaction scale.