31/05/2026
In September 2026, Japan's National Tax Agency replaces the system that has quietly run its enforcement for 25 years.
It's called KSK2 — and most taxpayers have never heard of it.
Here's the part that matters if any of your money, property, or income crosses a border:
KSK2 doesn't dig up new information about you. It makes the data the tax authority already receives far easier to match against your filings — overseas remittance reports, the ¥50M foreign-asset disclosure, and CRS-exchanged data on your foreign bank and brokerage accounts.
Tax types that used to sit in separate silos now sit in one view. Audit-target selection moves from a local examiner's intuition to nationwide, data-driven matching.
Two groups walk into this with the least cover:
→ Individuals filing alone, who assume modest foreign income or an overseas account stays below the radar.
→ Companies whose tax advisor handles domestic tax well but rarely touches cross-border issues — foreign shareholders, PE risk, transfer pricing, inbound/outbound payments.
The problem in both cases isn't dishonesty. It's blind spots — and KSK2 narrows the margin those blind spots used to enjoy.
The months before go-live are the time to make sure your Japanese filings, your overseas picture, and any foreign returns tell one coherent story.
At Tokyo Advisory we handle US and Japan filings in-house and represent clients through Japanese tax examinations. Full breakdown in the article 👇
https://www.tokyoadvisory.com/en/post/ksk2-goes-live-this-september-here-s-who-should-be-paying-attention
#税務
