New NISA Guide and the Power of Compounding｜30,000 Yen a Month for 20 Years
The new NISA lets you invest with tax-free profits. This guide covers the basics of the accumulation and growth frames, the 18 million yen lifetime limit, and why compounding grows your money, using concrete numbers.
Japan's renewed NISA program (the "new NISA"), launched in 2024, lets you invest while paying no tax on the profits (normally around 20%). If investing feels intimidating, understanding the basics of the system and why money tends to grow when you stay invested for the long term (the power of compounding) will help you make calmer decisions. This guide explains the essentials of the new NISA and the idea of compounding using concrete numbers.
What the new NISA is (two investment frames)
Think of NISA as a tax-advantaged account. Normally, profits from stocks and funds are taxed at about 20.315%. With NISA, profits earned inside the account are tax-free, so the full gain stays in your pocket. The new NISA has two frames you can use at the same time:
- Tsumitate (accumulation) frame, up to 1.2 million yen per year: low-cost index funds suited to long-term, regular, diversified investing. Ideal for beginners.
- Growth frame, up to 2.4 million yen per year: listed stocks and a wider range of funds.
Combined, you can invest up to 3.6 million yen per year. You may use one frame or both.
The 18 million yen lifetime limit and tax-free holding
A key feature is the lifetime investment limit of 18 million yen per person (of which the growth frame is capped at 12 million yen). There is no expiry on the tax-free status, so gains stay tax-free for as long as you hold. When you sell, the purchase-price portion of your lifetime allowance is restored the following year, so the allowance is not wasted even when life events require cash.
Why money grows through compounding
Compounding means profits earn further profits. Reinvesting gains instead of withdrawing them snowballs your balance over time. For example, 1 million yen at 5% per year grows to about 1.63 million yen in 10 years and about 2.65 million yen in 20 years with compounding, versus just 1.5 million yen with simple interest over 10 years. To run your own numbers, try our compound interest calculator.
Saving 30,000 yen a month for 20 years
Investing 30,000 yen monthly at an assumed 5% annual return for 20 years means a principal of 7.2 million yen and roughly 5.1 million yen in gains, for about 12.3 million yen in total. Inside the new NISA, those gains are tax-free. Change the amount or period with our NISA simulation tool. If you receive dividends, reinvesting them boosts compounding further; see the dividend simulation tool.
How to start (3 steps)
- Open a NISA account (one per person) at a brokerage; online brokers tend to offer wide choice and low fees.
- Choose your amount and fund; low-cost global or US index funds are common beginner choices.
- Automate the monthly purchase so you buy steadily regardless of timing (dollar-cost averaging).
Long-term mindset and risk notes
All investing carries risk and your balance can fall below your principal in the short term. Stay invested for the long run, diversify across many companies and countries, keep an emergency cash buffer, and remember the 5% figure here is only an assumption, not a guarantee.
This article is general information about the new NISA and investing and is not a recommendation to buy any specific product. Rules can change. Always confirm the latest details with official sources (Japan's FSA and National Tax Agency) and professionals such as your brokerage or a tax advisor. Invest at your own responsibility.
FAQ
Can beginners use the new NISA?
Yes. Pick a low-cost index fund in the accumulation frame and set up an automatic monthly purchase, so you do not have to worry about timing. You can start with small amounts.
What are the annual and lifetime limits?
Up to 3.6 million yen per year (1.2 million accumulation plus 2.4 million growth) and 18 million yen over your lifetime per person (growth frame capped at 12 million), all tax-free.
How strong is the compounding effect?
1 million yen at 5% grows to about 1.63 million yen in 10 years and 2.65 million yen in 20 years. The longer the period, the bigger the gap versus simple interest. Try our compound interest calculator.
How much is 30,000 yen a month for 20 years?
At an assumed 5% return, a principal of 7.2 million yen grows to roughly 12.3 million yen (about 5.1 million in gains). This is based on an assumed rate and is not guaranteed.
Can I lose money with the new NISA?
Yes. Because you invest in assets that fluctuate, your balance can fall below your principal in the short term. Stay long-term, diversified, and use spare cash you will not need soon.