Fixed income

Bond basics: How interest rates affect bond yields

May 09, 2023 - 6 min read

With steep tariff announcements causing economic uncertainty, along with stubborn inflation, the US Federal Reserve (Fed) decided at its May meeting to hold its benchmark interest rate steady at 4.25% to 4.50%. However, the Fed is still expected to cut rates a few times in 2025 into 2026. The Fed can lower or raise its short-term rate when needed to promote maximum employment and price stability, aiming to keep inflation at a healthy level in the 2% range.

Whether today’s higher-for-longer interest rate environment qualifies as good or bad news may depend on your point of view – and time horizon. Higher rates offer the potential for greater income and total return in the future. But when interest rates are cut, bond prices generally rise, as new bonds issued at lower interest rates become more attractive to investors. This makes existing bonds with higher interest rates less desirable, which decreases their price. So, now that there is attractive income potential in the bond markets, perhaps it is an opportune time to revisit some bond basics.

Bonds and interest rates

Bonds are debt securities issued by governments and corporations to fund their operations. Investors can purchase bonds from the issuer, who is then required to make interest payments on a regular schedule over a set number of years. (This is why bond investments are also known as fixed income.) The amount of interest paid reflects the prevailing interest rate environment at the time of issuance and is fixed over the life of the bond. This is where inflation concerns may enter the equation.

Bond prices, coupons, and yields

Regardless of whether a bond is issued by a government or a corporation, the mechanics of bond pricing are the same. Bonds are issued at a specific rate of interest that the issuer will pay to investors, known as the coupon. Once issued, the coupon never changes – but prevailing interest rates can. When that happens, an existing bond’s coupon rate may become more or less attractive by comparison, and that affects its price.

When an existing bond has a higher coupon than a newly issued bond, it pays out more income. Investors may be willing to pay more to own it, driving its market price up.
Conversely, when an existing bond has a lower coupon than current rates, investors may find it less appealing, and its market price may go down.

The relationship between a bond’s current price and its coupon is known as its yield, which is the amount of return an investor will realize on a bond, calculated by dividing its face value by its coupon. As market conditions affect a bond’s price, its yield will also change. For example:

As Bond Price Declines, Yield Increases

Source: Natixis Investment Managers

Government policies and interest rate decisions can significantly impact bond markets – affecting everything from yields to investor demand. Learn more about how recent policy shifts are influencing bond investing.

Understanding bond math

Understanding the relationship between bond prices and yields helps explain why bond investors can lose money based on the current price of their bonds, even though the interest income may help offset some of the price decline. When interest rates rise, prices of existing bonds tend to fall, even though the coupon rates remain constant, and yields go up. Conversely, when interest rates fall, prices of existing bonds tend to rise, their coupon remains constant – and yields go down.

Quality matters

Not surprisingly, a bond’s quality also has a direct bearing on its price and yield. Bonds are rated by independent agencies, with AAA/Aaa to BBB/Baa considered “investment grade.” These higher-quality bonds generally have a lower yield than non–investment grade or non-rated securities because they are considered more likely to make all of their scheduled interest payments. Conversely, lower rated or “high yield” bonds pay higher coupon rates because there is a greater possibility that the issuer could default and fail to make payments.

Fixed income investment options

Investors consider fixed income for different reasons: a low-risk anchor for their portfolio, diversification from equities, inflation, or interest rate concerns, among others. Actively managed fixed income mutual funds can invest in bonds, notes, and other securities issued by governments and corporations in the US and almost any country in the world. For example:

US government bonds are considered the highest quality and safest, as the US has never defaulted on its debt. Sovereign debt of other countries, such as emerging markets, may be riskier, depending on the country’s economic or political stability.
Corporate bonds, ranging from investment grade to high yield, are typically seen as somewhat riskier than US government bonds and may have higher interest rates to compensate for the additional risk.
Bank loans are debt issued to a company by a bank or similar financial institution and repackaged for sale to investors. As bank loans are typically secured by the issuer’s assets and rank senior to the company’s other debt, they are considered less risky than other fixed income bonds. They sometimes offer a floating rate feature, where the adjusting rate can be helpful in a rising interest rate environment.
Municipal bonds are issued by a state, municipality, or county to finance its capital expenditures (construction of bridges, highways, schools). They are exempt from federal taxes and thus attractive to high income investors.
TIPS, or Treasury Inflation-Protected Securities, are bonds issued by the US government wherein the principal value increases in line with inflation changes. They aim to protect investors from a loss of purchasing power due to inflation.

Choosing the right bond fund

Specific bond funds may offer one of the fixed income instruments listed above or some combination thereof. Multisector funds, for example, make tactical allocations to different sectors for added return potential and may help to hedge against interest rate or volatility risk. Bond funds are offered across an array of risk/return objectives, credit quality (investment grade or high yield), and the desired duration of income needs, from short-term to long-term investments, perhaps for retirement. Funds may also satisfy investors’ desire to support sustainability by integrating ESG (environmental, social, and governance) considerations into the investment manager’s research and decision-making process.

A fund’s specific investments can vary widely based on the fund’s investment style, risk/return objectives, benchmark, and other factors. As a result, some fixed income funds may tend to be more stable, while others have greater potential for price fluctuations and growth.

With so many variables to consider, most financial advisors recommend actively managed fixed income mutual funds for their clients rather than individual bonds. Active bond funds offer experienced professional managers a specified investment objective, diversification, and daily liquidity. For investors seeking exposure to certain fixed income indices, sectors, duration ranges, etc., the flexibility of actively managed ETFs may be a consideration.

Be sure to reach out to your financial advisor to discuss the right mix of fixed income investments for your needs. Depending on your age, risk tolerance, and overall income needs, your advisor can help you maintain an appropriate level of income diversification in your portfolio.

Understanding the bond market is essential for making informed investment decisions. Our fixed income insights provide ongoing analysis of economic drivers, yield trends, and investment opportunities.

All investing involves risk, including the risk of loss. Investment risk exists with equity, fixed income, and alternative investments. There is no assurance that any investment will meet its performance objectives or that losses will be avoided.

Fixed income securities may carry one or more of the following risks: credit, interest rate (as interest rates rise, bond prices usually fall), inflation and liquidity.

Mortgage-related and asset-backed securities are subject to the risks of the mortgages and assets underlying the securities. Other related risks include prepayment risk, which is the risk that the securities may be prepaid, potentially resulting in the reinvestment of the prepaid amounts into securities with lower yields.

Below investment grade fixed income securities may be subject to greater risks (including the risk of default) than other fixed income securities.

Foreign and emerging market securities may be subject to greater political, economic, environmental, credit, currency and information risks. Foreign securities may be subject to higher volatility than US securities due to varying degrees of regulation and limited liquidity. These risks are magnified in emerging markets.

Currency exchange rates between the US dollar and foreign currencies may cause the value of the fund's investments to decline.

Inflation-protected securities move with the rate of inflation and carry the risk that in deflationary conditions (when inflation is negative), the value of the bond may decrease.

An exchange-traded fund, or ETF, is a marketable security that tracks an index, commodity, bond, or a basket of assets like an index fund. ETFs trade like common stock on a stock exchange and experience price fluctuations throughout the day as they are bought and sold. Short-term fixed income ETFs invest in fixed income securities with durations between one and five years.

Unlike passive investments, there are no indexes that an active investment attempts to track or replicate. Thus, the ability of an active investment to achieve its objectives will depend on the effectiveness of the investment manager.

Sustainable investing focuses on investments in companies that relate to certain sustainable development themes and demonstrate adherence to environmental, social and governance (ESG) practices; therefore, the universe of investments may be limited, and investors may not be able to take advantage of the same opportunities or market trends as investors that do not use such criteria. This could have a negative impact on an investor's overall performance depending on whether such investments are in or out of favor.

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