NISA Calculator

The New NISA, launched January 2024, is Japan's tax-free investment account. It lets you invest up to ¥3.6 million per year (¥18 million lifetime) in stocks and mutual funds without paying any tax on capital gains or dividends — permanently. It has two parts: the Tsumitate portion (¥1.2M/year, regular investment funds) and the Growth portion (¥2.4M/year, individual stocks + funds).

Japan taxes investment gains at 20.315% (15% national tax + 5% resident tax + 0.315% reconstruction surtax). With NISA, that rate becomes 0% — forever. Importantly, in a Japanese taxable account (特定口座), you only pay this tax when you sell — not every year. This deferred taxation means your money compounds faster than annual taxation would suggest. Over 20 years at 5% return with ¥50K/month, NISA saves you approximately ¥1.75 million in taxes.

Because Japanese capital gains tax is deferred — you only pay when you sell. During the accumulation phase, both NISA and taxable accounts grow at the same rate. The tax is calculated once at the end on your total gain. Many calculators incorrectly apply annual tax, which creates artificial 'tax drag' and understates your taxable account value. We show the legally accurate deferred method.

Yes. There are no lock-up periods or withdrawal restrictions on New NISA. Your lifetime contribution limit tracks book value (purchase amount), not current market value. When you withdraw, the used portion of your ¥18M lifetime limit becomes available again — this is the reusable framework unique to New NISA.

They serve different purposes. iDeCo (個人型確定拠出年金) gives you an income tax deduction on contributions (saving ~15-45%) but locks money until age 60. NISA gives no tax deduction but all gains are tax-free and you can withdraw anytime. Rule of thumb: if you need money before 60, prioritize NISA. If you can wait until 60 and want current tax reduction, iDeCo is powerful. Using both is ideal.