# Convertible Bonds: Bond Floor, Conversion Option, and Dilution

Understand how convertible bonds combine debt and equity exposure, why they can move with credit, rates, volatility, and stock price, and how conversion may dilute shareholders.

Canonical: https://wiki.fcontext.com/stocks/convertible-bond/
Fact checked: 2026-07-14

> For educational purposes only; not investment advice.

<a id="answer"></a>

## Direct answer

A **convertible bond** is a corporate bond that can be converted into a specified number of shares under stated conditions. It is often described as a bond plus an equity option: the bond side provides coupon, maturity, and credit exposure; the conversion feature gives potential participation if the stock rises.

That hybrid nature is the point. Convertibles are not simply safer stocks or higher-yielding bonds. Their value can respond to interest rates, credit spreads, stock price, stock volatility, call terms, and expected dilution.

<a id="mechanism"></a>

## How it works

The key terms are the **conversion ratio** and **conversion price**. If a $1,000 bond converts into 20 shares, the conversion price is $50 per share. When the stock trades far below $50, the bond may behave more like credit. When the stock trades far above $50, it may behave more like equity.

The **bond floor** is the approximate value of the instrument as a straight bond without the conversion option. It depends on coupon, maturity, interest rates, credit quality, and seniority. The conversion option adds value when the stock has upside potential or high expected volatility.

Issuers may include call provisions, forced-conversion features, or settlement choices. For common shareholders, conversion can increase the share count and reduce EPS if the new shares are included in diluted calculations.

<a id="example"></a>

## Example

Assume a company issues a $1,000 convertible bond with a 2% coupon and a conversion ratio of 20 shares. The implied conversion price is:

`$1,000 ÷ 20 = $50`

If the stock is $35, the conversion value is $700, so investors focus on credit quality, coupon, and bond floor. If the stock rises to $70, the conversion value is $1,400, and the bond may trade with much more equity sensitivity. If many bonds convert, the company may reduce debt but issue new shares, diluting existing holders.

<a id="risks"></a>

## Risks

- **Credit risk:** The issuer may weaken or default, reducing the bond floor.
- **Interest-rate risk:** Higher rates can lower the value of the bond component.
- **Equity risk:** If the stock falls or never reaches the conversion price, the option may be worth little.
- **Volatility risk:** The option component depends partly on expected volatility.
- **Call risk:** Issuer call provisions can limit upside or force a decision at an inconvenient time.
- **Dilution risk:** Conversion can increase shares outstanding and reduce per-share metrics.

<a id="misconceptions"></a>

## Common misconceptions

A convertible bond is not guaranteed downside protection. The bond floor can fall if credit quality deteriorates.

Low coupon does not mean low risk. Investors are often accepting a lower coupon in exchange for equity optionality.

Conversion is not always good for existing shareholders. It can reduce leverage, but it can also dilute ownership and EPS.

<a id="related"></a>

## Related topics

- [Common Stock](/stocks/common-stock/)
- [Bond Duration](/stocks/bond-duration/)
- [Earnings per Share](/stocks/eps/)

<a id="sources"></a>

## Sources

- SEC: 10-K disclosure framework for debt, equity, dilution, and risk factors.
- FINRA: bond characteristics, call provisions, credit risk, and interest-rate risk.
- Journal of Finance: classic valuation research on corporate securities and indenture provisions.