# What Is a Bond Fund? How It Works, Benefits, Taxes, and Types

> **Definition**
>
> A bond fund is a mutual fund or ETF that invests primarily in government and corporate bonds.

## What Is a Bond Fund?

A bond fund is a [mutual fund](https://www.investopedia.com/mutual-funds-types-strategies-8611142) or an [exchange-traded fund](https://www.investopedia.com/terms/e/etf.asp) (ETF) that buys and sells debt instruments like government and corporate bonds. The primary goal of a bond fund is to generate monthly income for investors.

For an investor, a bond fund is an alternative to buying individual bonds. The investor in a bond fund is buying shares in a fund that buys and sells many bonds. Typically, a bond [fund manager](https://www.investopedia.com/terms/f/fundmanager.asp) buys and sells according to market conditions and rarely holds bonds until maturity.

### Key Takeaways

*   A bond fund invests primarily in a portfolio of fixed-income securities such as municipal and corporate bonds.
*   Bond funds provide diversification with a low required minimum investment.
*   Due to the inverse relationship between interest rates and bond prices, a long-term bond has greater interest rate risk than a short-term bond.

## Understanding Bond Funds

For many investors, a bond fund is a more efficient way of investing than buying individual bond securities. Unlike individual bond securities, bond funds do not have a [maturity date](https://www.investopedia.com/terms/m/maturitydate.asp) for the repayment of principal, so the principal amount invested may fluctuate from time to time.

Investors in bond funds receive monthly payments that reflect the mix of all the bonds in the fund, which means that the interest income payment will vary monthly.

### What "AAA" Means

Bonds are rated according to the degree of risk that their issuers will default on their debts. An "AAA" or "AA" bond is issued by a company or government that is highly unlikely to default.

## Types of Bond Funds

Most bond funds are comprised of a certain type of bond, such as [corporate](https://www.investopedia.com/terms/c/corporatebond.asp) or [government bonds](https://www.investopedia.com/terms/g/government-bond.asp).

They also focus on the time to maturity, such as [short-term, intermediate-term, and long-term](https://www.investopedia.com/invest-for-short-term-and-long-term-goals-8347417).

Investors can choose bond funds that buy only the highest-quality and safest bonds, such as U.S. government bonds or the bonds of blue-chip companies. High-quality bonds pay lower interest than riskier bonds.

Investors should note that U.S. government bonds are considered to be of the highest credit quality. Bond funds that specialize in U.S. Treasury securities, including [Treasury inflation-protected securities](https://www.investopedia.com/terms/t/tips.asp) (TIPS), are the safest but offer the lowest potential return.

### Riskier Choices

Other funds invest in only riskier bonds—high-yield or [junk bonds](https://www.investopedia.com/terms/j/junkbond.asp). Bond funds that invest in riskier bonds offer higher returns along with a higher risk of default by the bond issuer.

There are also bond funds that have a mix of the different types of bonds to create [multi-asset class](https://www.investopedia.com/terms/m/multiasset_class.asp) options.

The types of funds available include US government bond funds, municipal bond funds, corporate bond funds, mortgage-backed securities (MBS) funds, high-yield bond funds, emerging market bond funds, and [global bond funds](https://www.investopedia.com/articles/investing/010616/top-5-global-bond-funds-2016.asp).

> **Fast Fact**
>
> Mutual funds have been investing in bonds for many years. Some of the oldest balanced funds, which include allocations to both stock and bonds, date back to the late 1920s.

## Bond Fund Benefits

Bond funds are an attractive option compared to buying individual bonds. They provide greater portfolio diversification than an individual investor could manage independently.

By investing in a bond fund, an investor only needs to pay the [annual expense ratio](https://www.investopedia.com/terms/t/ter.asp) that covers marketing, administrative, and professional management fees. The alternative is to purchase multiple bonds separately and deal with the [transaction costs](https://www.investopedia.com/terms/t/transactioncosts.asp) associated with each.

Since a fund usually invests in many bonds of varying maturities, the impact of any single bond’s performance is lessened.

Another benefit of a bond mutual fund is that it provides access to professional portfolio managers with the expertise to research and analyze the [creditworthiness](https://www.investopedia.com/terms/c/credit-worthiness.asp) of bond issuers and market conditions before buying into or selling out of the fund.

For example, a fund manager may replace bonds when the issuer's [credit is downgraded](https://www.investopedia.com/terms/d/downgrade.asp) or when the issuer "calls," or pays off the bond, before its maturity date.

## Special Considerations

Bond funds can be sold at any time for their current market [net asset value](https://www.investopedia.com/terms/n/nav.asp) (NAV), which may result in a capital gain or loss. Individual bonds can be harder to unload.

From a tax perspective, some investors in higher tax brackets may find that they have a higher [after-tax yield](https://www.investopedia.com/terms/a/after_tax_return.asp) from a tax-free municipal bond fund investment rather than a taxable bond fund investment.

Due to the [inverse relationship between interest rates and bond prices](https://www.investopedia.com/articles/investing/101215/how-interest-rates-affect-mutual-funds.asp), a long-term bond carries greater [interest rate risk](https://www.investopedia.com/terms/i/interestraterisk.asp) than a short-term bond. Therefore, the NAV of bond funds with longer-term maturities will be impacted greatly by changes in interest rates. This, in turn, will affect how much interest income the fund can distribute to its participants monthly.

## Bond ETFs

Bond ETFs have been around for less time than bond mutual funds, with [iShares](https://www.investopedia.com/terms/i/ishares.asp) launching the first bond ETF fund in 2002. Most of these offerings seek to replicate various bond [indices](https://www.investopedia.com/terms/i/index.asp), although a growing number of actively managed products are also available.

[ETFs](https://www.investopedia.com/terms/e/etf.asp) often have lower fees than their mutual fund counterparts. Like stocks, ETFs trade throughout the day. The prices for shares can fluctuate moment by moment and may vary quite a bit over the course of a day's trading.

Bond ETFs operate much like [closed-end funds](https://www.investopedia.com/terms/c/closed-endinvestment.asp), in that they are purchased through a brokerage account rather than directly from a fund company.

When the investor wishes to sell, ETFs must be traded on the open market. The fund company will not purchase the shares, as is done for open-ended mutual funds.

## Explain Like I'm Five

A bond fund is a mutual fund or ETF that invests in bonds instead of stocks. They can invest in Treasury bonds, municipal bonds, or corporate bonds. Some bond funds only invest in the safest bonds, and some invest in junk bonds with higher returns.

Buying a bond fund allows you to get exposure to a large basket of bonds, without having to research the characteristics of each individual bond. Bonds are considered relatively safe, but they are sensitive to interest rate changes. The value of a bond fund can fall when interest rates go up.  

## What Types of Bond ETFs Are There?

There is a wide variety of bond ETFs and bond mutual funds to choose from. They include funds that invest in California municipal bonds, U.S. or international government bonds, investment-grade corporate bonds, and tax-exempt bonds. Funds may invest in short-term, medium-term, or long-term bonds.

## What Are Some Large Bond ETFs?

Three large bond ETFs are iShares Core U.S. Aggregate Bond ETF (AGG), Vanguard Total Bond Market ETF (BND), and Vanguard Total International Bond ETF (BNDX).

## How Can I Invest in a Bond Fund?

To invest in a bond fund, you will need an online brokerage account, such as at Fidelity, E\*Trade, or Charles Schwab, for example. From there, transfer money into your brokerage account so that you're able to purchase a bond fund. Determine what kind of bond fund you'd like to buy, for example, a corporate bond fund, a government bond fund, a bond index fund, etc. Decide on the type, whether a mutual fund or exchange-traded fund, look up the ticker, and buy shares of the fund.  

## The Bottom Line

Bond ETFs and bond mutual funds are an alternative to individual bond-picking for the investor interested in a steady stream of income.

Like bonds, bond funds are generally a choice for the conservative investor. As with any investment, a little more risk has the potential for a relatively larger return.

> **Article Sources**
>
> 1.  U.S. Securities and Exchange Commission. "[Bond Funds and Income Funds](https://www.investor.gov/introduction-investing/investing-basics/glossary/bond-funds-and-income-funds)."
>     
> 2.  American Economic Association. "[What Makes US Government Bonds Safe Assets?](https://www.aeaweb.org/articles?id=10.1257/aer.p20161109)"
>     
> 3.  Financial Industry Regulatory Authority. "[Bonds](https://www.finra.org/investors/investing/investment-products/bonds)."
>     
> 4.  iShares. "[Bonds Still have a Big Role to Play in Portfolios](https://www.ishares.com/us/insights/investing-strategies-bond-etfs)."
>     
> 5.  U.S. Securities and Exchange Commission. "[Investor Bulletin: Exchange-Traded Funds (ETFs)](https://www.sec.gov/investor/alerts/etfs.pdf)."
>     
> 6.  VettaFi. "[Bond ETF List](https://etfdb.com/etfs/asset-class/bond/)."