Bond Pricing Explained
How bond prices are determined and why they move when interest rates change
The core idea behind bond pricing
At its core, a bond is simple.
It is a stream of future cash flows:
Periodic coupon payments
A final principal repayment
The price of a bond is the present value of those future cash flows.
That means:
👉 every payment is discounted back to today
👉 using the current market interest rate (yield)
Why bond prices fall when rates rise
This is the most important relationship in fixed income:
👉 Bond prices and yields move in opposite directions
Here’s why:
If new bonds are issued with higher yields, older bonds with lower coupons become less attractive. To compensate, their price must fall until their effective yield matches the market.
Example:
Existing bond pays 2%
New bonds pay 4%
👉 No one buys the 2% bond at full price
👉 its price drops until yield adjusts
Simple pricing example
Assume:
Face value: $1,000
Coupon: 3%
Market yield rises to 5%
The bond must trade below $1,000 so that its effective return matches 5%.
👉 This is how pricing adjusts automatically.
The role of yield
Yield is not just a number. It is the discount rate that determines the price of the bond.
Different yields reflect:
Inflation expectations
Central bank policy
Credit risk
Liquidity conditions
When yield changes, the entire pricing mechanism shifts.
Duration: the missing link in bond pricing
Bond pricing explains why prices move. Duration explains how much they move.
This is the connection:
Pricing = mechanism
Duration = sensitivity
Example:
If yields rise by 1%:
Low duration bond → small price change
High duration bond → large price change
Try it yourself
Use the Duration Lab to see how bond prices change with different rate scenarios.
What affects bond prices
Several factors influence bond pricing:
1. Interest rates
The most important driver.
Higher rates → lower prices
Lower rates → higher prices
2. Time to maturity
Longer bonds are more sensitive to rate changes.
3. Coupon rate
Lower coupons → higher sensitivity
Higher coupons → lower sensitivity
4. Credit risk
Higher risk → higher yield → lower price
5. Market liquidity
Less liquidity → higher required yield
Premium vs discount bonds
Bonds do not always trade at face value.
Premium bond
Price > face value
Coupon > market yield
Discount bond
Price < face value
Coupon < market yield
👉 Pricing adjusts so yield aligns with the market.
Why bond pricing matters for investors
Bond pricing is not just theory.
It directly impacts:
Portfolio value
Risk exposure
Performance during rate changes
Many investors focus on income but price changes often matter more.
Especially when:
Rates move quickly
Duration is high
Common mistakes
❌ Ignoring price volatility
Bonds can move significantly, especially with high duration.
❌ Focusing only on yield
Yield does not show downside risk.
❌ Assuming bonds are “safe”
They are rate-sensitive assets.
Bond pricing in today’s market
Bond pricing becomes more important when:
Inflation is unstable
Central banks are active
Yields are volatile
Global flows are shifting
In these environments:
Pricing moves faster
Duration matters more
Putting it all together
Bond pricing connects everything:
Yields
Duration
Macro conditions
Market behavior
Understanding pricing means to understand how markets actually move.