What it means
A convertible is a hybrid security, which means it combines features of debt and equity. The most common form is a convertible bond or convertible note, which pays regular interest and returns its face value at maturity unless the holder converts it into shares first.
Convertible preferred shares work in a similar way, but they pay a fixed dividend instead of interest. Companies issue convertibles because they can often borrow at a lower interest rate than they would pay on straight debt.
The conversion feature is the sweetener that makes the instrument attractive, since investors accept a lower coupon in return for the right to buy shares later. For the company, a successful conversion removes the debt from the balance sheet without a cash repayment.
The key figure is the conversion price, which is the price per share at which the holder can convert. If the share price rises well above the conversion price, the holder usually converts and the value of the conversion right becomes substantial.
If the share price stays below it, the holder normally keeps the bond and collects interest, so the instrument behaves much like ordinary debt. Finance teams need to track convertibles carefully because conversion dilutes existing shareholders.
Depending on the accounting framework and the terms, the instrument may be split into a debt part and an equity part on the balance sheet. Analysts therefore look at the fully diluted share count, which assumes all convertibles have been converted, rather than the current number of shares in issue.
A common variant is the convertible with a forced conversion clause, which lets the company require conversion once the share price has stayed above a set level for a defined period. Investors should also check whether the conversion price resets if the company later raises money at a lower price, because anti-dilution terms change the outcome.
Convertibles are a useful financing tool, but the detailed terms decide who benefits.
In practice
Real-world examples.
Example
A software start-up raises a $2 million round through convertible notes that convert at a 20% discount to the price paid by the next equity investors. The founders run a dilution model before signing, because each conversion adds shares that reduce their own stake. The model shows how much of the company they keep under each possible share price.
Example
A regional bakery chain issues $1,200,000 of convertible bonds to fund four new shops. The finance team tracks the conversion price against the share price each quarter, because a rising share price would make bondholders convert and dilute the founding family. The board considers adding a call option so it can force conversion if the price stays strong.
Example
An investment fund holds $50,000 of convertible preferred shares in a listed logistics company. Its analyst compares the fixed dividend with the current interest rate on the company's bonds to judge whether the holding is worth keeping. The analyst also checks how many ordinary shares the preferred would convert into if the company's share price doubled.
Formula
Calculation
Shares received on conversion = Face value of the convertible / Conversion price per share
Suppose a company issues a $500,000 convertible note with a conversion price of $25 per share. The holder can convert the full face value into shares, so the shares received equal $500,000 / $25 = 20,000 shares. If the share price later reaches $40, those 20,000 shares are worth $800,000 (20,000 x $40), which is $300,000 more than the note's face value of $500,000 before any interest is counted.Case study
Seen in the real world.
This illustrative case follows Brightwater Snacks, a fictional mid-sized food maker that needs $1,500,000 to build a second production line. Its bank will lend only at a high rate, so the board issues a convertible note with a 5% coupon and a conversion price of $4 per share. The founders accept the dilution risk because they expect the new line to lift profits and the share price.
Two years later the share price has risen to $6, and the holder converts the full note. The note turns into 375,000 shares ($1,500,000 / $4), and the investor's stake is now worth $2,250,000 (375,000 x $6) rather than the $1,500,000 it lent. The company avoids a cash repayment, but its existing shareholders now own a smaller percentage of the business.
Watch out
Common mistakes.
- Treating a convertible as pure debt and ignoring the equity option, which can make the company look less diluted than it will be once conversion happens.
- Quoting the current share count and forgetting the shares that would be issued on conversion, which understates the true ownership picture.
- Assuming every convertible will convert, when a share price below the conversion price usually means the holder keeps the bond and expects repayment.
Questions
People also ask.
When does a convertible actually convert?
It converts when the holder chooses to, which is usually when the share price is above the conversion price so the shares are worth more than the face value.
Is a convertible the same as a warrant?
No, a warrant is a standalone right to buy shares at a set price, whereas a convertible is a security that turns into shares when the holder converts it.
How should a non-finance manager read a convertible in a board pack?
Focus on the fully diluted share count, the conversion price and the maturity date, because those three figures show future dilution and the timing of any repayment.
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