Looking for a safe investment lately, many people have started to take an interest in how to buy U.S. bonds. Because of the belief that the U.S. government guarantees repayment, U.S. bonds are considered a flagship safe asset. Although the nominal interest rate is low, the ability to cash out at any time makes them attractive.

Let's start by thinking about what bonds are. Basically, bonds are similar to debt certificates. Investors lend money and receive the principal back on a set maturity date. During this process, the debtor usually pays interest every six months or annually. The government is the same; if it lacks funds needed for national operations, it issues government bonds to borrow money from institutions or individuals.

There are three types of bonds issued by the U.S. Department of the Treasury. T-bills are short-term securities under one year, with almost no risk and high liquidity. T-notes are medium-term securities from 1 to 10 years, and T-bonds are long-term securities from 10 to 30 years. During uncertain economic times, stable government bonds play an important role in a portfolio.

The relationship between bond interest rates and yields is somewhat unique. In the market, bond prices and interest rates move inversely. When demand for Treasury bonds increases, prices go up and interest rates go down; when demand decreases, prices fall and interest rates rise. Ultimately, bond yields reflect investor sentiment.

The advantages of investing in U.S. bonds include first, excellent safety. Because the U.S. government guarantees repayment, the risk of default is almost nonexistent. Second, predictable returns. Fixed interest rates are set at issuance, and interest is paid regularly every six months, making them ideal for retirees. Third, high liquidity. U.S. Treasuries are actively traded in the bond market, so they can be easily sold when needed. Fourth, tax benefits—interest on government bonds is subject to federal tax but exempt from state and local taxes, potentially increasing after-tax returns.

Of course, there are risks. When interest rates rise, the value of existing bonds falls. If you need to sell before maturity, you could incur losses. Inflation is also a concern; since fixed interest rates may not keep pace with rising prices. For foreign investors, exchange rate fluctuations matter too. A weakening dollar can reduce returns when converted back to local currency. Lastly, there is credit risk—though theoretically the U.S. government might default, in practice, the risk is extremely low.

There are three main ways to buy U.S. bonds. The first is direct purchase. You can buy and sell Treasury securities directly from the U.S. Department of the Treasury via the TreasuryDirect website. The advantage is no management fees, and you receive interest regularly if you hold until maturity. The downside is that individual investment amounts are limited to a maximum of $10k. To diversify, you need to buy multiple bonds, which requires considerable management.

The second method is bond funds. These pool money from multiple investors to buy a diversified portfolio of bonds managed by professionals. This reduces risk associated with individual bonds and allows investment with smaller amounts, but management fees can lower overall returns.

The third is bond index funds or ETFs. These track specific bond indices, generally offering lower costs than actively managed funds. They can be bought and sold on stock exchanges, providing high flexibility, but are subject to market volatility and tracking errors relative to the underlying index.

For Korean investors, considering both Korean bonds and U.S. bonds makes sense. Diversifying across both markets can reduce risk through geographic and currency diversification. Holding bonds denominated in won and dollars can offset some currency risk. Since the economic cycles of Korea and the U.S. don't always align, a downturn in one economy can be offset by growth in the other.

From a yield optimization perspective, you can also utilize the yield curves of both countries. If Korean bonds offer higher yields, you might keep U.S. bonds as core assets for stability while increasing Korean bond holdings to boost returns.

The most critical concern for Korean investors in U.S. bonds is exchange rate risk. Fluctuations in the dollar exchange rate affect returns when converting back to won. Hedging via forward contracts or derivatives can lock in exchange rates, reducing volatility, but this can also decrease overall returns due to hedging costs. Alternatively, some portion of the investment can be hedged while leaving the rest exposed.

Duration is also important; it indicates a bond’s sensitivity to interest rate changes. If preserving principal over the long term is the goal, a portfolio composed of long-term U.S. Treasuries can provide stable returns. Conversely, including bonds with shorter durations can reduce sensitivity to interest rate fluctuations.

Tax considerations are essential. Interest income from U.S. government bonds is taxable at the federal level but may also be taxed in Korea. Fortunately, Korea and the U.S. have a double taxation treaty, preventing double taxation on the same income. Consulting a tax professional to understand specific tax implications is advisable.

For example, a balanced portfolio with 50% Korean bonds and 50% U.S. bonds aims to achieve both principal preservation and income generation. It reduces dependence on a single economy. When the dollar is strong, the unhedged portion of U.S. bonds can yield high returns when converted to won; when the dollar weakens, the hedged portion can offset currency losses.

In conclusion, how to buy U.S. bonds depends on individual investment goals and risk tolerance. Whether through direct purchase, bond funds, or ETFs, the key is to develop a strategy suited to your situation. For Korean investors, diversifying across U.S. and Korean bonds can enhance portfolio diversification and income stability. Understanding interest rate, inflation, and currency risks thoroughly can lead to more stable income opportunities.