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Bullstory Research July 9, 2026

Merely in name only 10the betrayal of a savings plan with an interest rate, and the real way to invest that brings forward financial freedom

Key takeaways

An annual 10savings plan at percent looks like monthly installment deposits, but the amount actually received is cut to nearly half compared with the nominal rate, and after interest income tax of 15.4percent is taken, the real profit is even smaller. The solution is to steadily add S and P 500and Nasdaq ETFs in an ISA, accelerating assets through tax benefits and compounding by unit. With automatic buying and the use of exchange-rate gains to remove emotion, the speed of reaching the target assets increases.

The stock market may seem full of different types and complicated, but can someone like me, who has only saved through deposit accounts, really enter it? In today’s article, we will dig into the truth about deposit-account interest and cover everything from the basic concept of ETFs that even stock beginners can follow easily to representative holdings 3, and 1the practical setup method that will explosively increase the speed to reaching the hundred-million mark (ISA & 250tax-free ten-thousand-won investment) to complete perfection.

1. Fact check: the real reason the interest that reaches my bank account gets cut in half

"A special deposit offer with an annual 10% rate!" You’ve probably seen ads like this from banks many times. But when maturity comes and you actually receive the interest, you end up disappointed by an amount that is much smaller than expected. The reason is that banks do not pay interest for 1 years on the entire principal you have saved.

Let’s assume you deposit 100won every month for 1 years.

  • The 100won deposited in the first month earns interest for the full 12 months.

  • But the 12month contribution of 100won only earns interest for a mere 1 months.

Ultimately, the effective interest rate of a savings deposit calculated with simple interest drops to nearly half of the nominal rate. On top of this capital gains tax 15.4is deducted, and once inflation is taken out as well, it is effectively the same as my assets melting away. This is exactly why I need to break the savings deposit and start investing.

2. ETFs, a ‘complete starter kit’ for stock market beginners (own the whole market)

If you feel lost about which stock to buy, an ETF (exchange-traded fund) is the answer, letting you put the ‘whole market’ into one basket instead of picking individual companies.

An ETF is a magic basket designed so you can buy and sell it easily in the stock market. For example, if you buy just one ETF that invests in the entire U.S. market, your money is automatically split and diversified across hundreds of companies around the world, including Apple, Microsoft, Nvidia, and others. 1Even if a few companies wobble, other high-quality companies in the basket firmly defend your account, so you can ride the long-term upward trend of capitalism with peace of mind, without having to stress over bad news in individual names.

3. Practical deployment! Global 3-stock index ETFs worth putting into my account

As long as the correlations among assets are different, increasing the number of holdings in a portfolio is by no means risky. Here are representative ETFs that track the 3-stock indices at the center of global capital.

  • S&P 500 (VOO, SPY)****: Warren Buffett praised this as the classic approach to investing. Invest in American business itself by holding all of the top 500high-quality companies in the United States.

  • Nasdaq 100 (QQQ, QQQM): Concentrate your investment on 100 American growth stocks with overwhelming technology and ideas that lead the world. In particular, before you have built a seed capital of 1 won, it is effective to increase expected returns by focusing on Nasdaq tech stocks with unmatched monopoly power and originality in the market.

  • Dow Jones 30 (DIA, SCHD): This is a basket that selects and holds only 30 top-tier blue-chip companies with the longest history in the U.S. stock market. With relatively low volatility, it serves as a strong defender in the portfolio.

4. ISA account use: Representative index ETF lineup

These are representative ETF names that you can accumulate conveniently on domestic exchanges while enjoying tax-free benefits. Within an ISA account, combine the following names to build 'your own portfolio'.

These securities can be bought in real time on domestic brokerage apps, and by contributing up to 2,000ten thousand won per year, you can fully enjoy the tax-free and separate taxation benefits on the returns generated.

Please compare each ETF by focusing on the differences in fees and trading volume, then buy if appropriate.

5. Two-track strategy to speed up economic freedom: [ISA + stock accumulation]

There is no need to be tied to complicated preferential-rate conditions. The tax-saving effect of ISA and tax exemption on overseas stocks95 can be used4 at the same99 time8 with a two-track88 strategy9 that90 combines2 these95 benefits84 and8 saves8 on88 taxes0 on88 U.0S.98 stocks9 and1 the9 tax-saving4 effect84 of9 ETF4 tax8 savings94 and3 the84 tax2 exemption8 on84 overseas4 stocks3.84 That99 is84 enough0.84 A0 two-track80 strategy9 that4 uses93 both9 benefits-2026 at once.

️ Strategy 1: With an ISA account, annual 2,000won Fill it up

By diversifying each month, contribute up to 2,000won a year into your ISA account and steadily build up S&P 500or Nasdaq 100ETFs such as TIGER/ACE. With the profit-and-loss offset benefit and the tax-free limit, you can prevent tax leakage and build the basic foundation of seed money in the most stable way.

Strategy 2: Use a direct overseas stock-purchase account to buy VOO and QQQ every day or every week (250won tax-free)

Use any extra cash beyond ISA contributions through a direct overseas stock-purchase account. Buy VOO, QQQ, and similar products on a daily or weekly basis through the brokerage’s automatic purchase function to overcome market volatility through time diversification. The key is to lock in 250won in annual profit. At the end of each year, sell and immediately repurchase up to 250won of gains to make the most of the tax-free limit every year.

** Don’t miss this! ‘exchange-rate gains’ — a hidden bonus**

The most powerful weapon in a strategy of directly accumulating overseas stocks is exchange-rate gains. When a crisis hits and the stock market shakes, the value of the safe-haven dollar soars. In other words, the decline in stock prices is either perfectly offset by the rise in dollar value, or even produces a 'hidden bonus' return that lifts the overall return. This is an overwhelming advantage that only overseas stock investors can enjoy, and one that people holding only won-based assets cannot.

In closing

Break free from savings accounts that are slowly eroded by exchange rates and start the magic of compounding through share accumulation with emotion-free “automatic stock investing.” S&P 500 and Nasdaq, properly combined, and with ISA and tax-free deduction benefits as your two wings? A perfect “snowball portfolio” will be complete, allowing you to roll your own snowball to achieve financial freedom the fastest, while sleeping soundly and peacefully no matter what downturn arrives!

Frequently asked questions

Is a savings plan with annual 10percent interest in name only actually a loss? How do you calculate the post-tax real interest rate?

The annual 10percent advertised rate falls to nearly half the actual average interest rate when monthly installment deposits are taken into account. Subtract the interest income tax of 15.4percent here, and you get the real return.

10The trap in savings-account ads: how do you calculate the actual return after factoring in taxes, fees, and inflation?

The actual return can be calculated by subtracting from the nominal rate the drop in the average interest rate caused by monthly deposits, the interest income tax 15.4%, and inflation.

What low-risk, medium-return investment mix could a beginner realistically try instead of a savings account paying 10%?

In an ISA, with an annual 2,000won limit, steadily hold S&P500-family ETFs, and diversify surplus funds with automatic overseas buys of VOO and QQQ; this is a realistic mix.

When moving from savings accounts to stocks and ETFs, how should exchange rates and taxes be considered?

Keep in mind the exchange gain that dollar strength can offset when share prices fall, and use the ISA (annual 2,000won) and the overseas annual 250tax-free allowance to reduce tax leakage.

10What is the checklist for the hidden conditions of a percent savings deposit, such as early withdrawal penalties and preferred interest-rate conditions?

First check the preferred interest-rate eligibility requirements, payment schedule, and early withdrawal penalty, then calculate the effective monthly interest and compare it with alternative investments.