Yield to maturity (YTM) is the total return you would earn on a bond if you bought it today at the current market price, held it until maturity, and reinvested all coupon payments at the same rate. It is the most comprehensive single measure of a bond’s return — more useful than the coupon rate alone.
Why the Coupon Rate Alone Is Insufficient
A bond’s coupon rate is fixed at issue — it describes the annual interest payment as a percentage of the face value. But bonds trade at prices above and below face value on the secondary market.
Example: A 10-year AGB with a 3.00% coupon and $1,000 face value was issued when rates were 3%. Now rates have risen to 5%. The bond’s price has fallen to approximately $845 on the market, so new buyers get:
- The same $30/year coupon ($1,000 × 3%)
- Plus the $155 capital gain at maturity ($1,000 - $845)
- Total return: approximately 5% per year = the current yield to maturity
The coupon rate (3%) understates the true return for someone buying today. YTM (5%) captures the complete picture.
How to Calculate YTM
YTM is the discount rate that equates the present value of all future cash flows (coupons + face value) to the current market price. The formula requires iteration (trial and error) or a financial calculator:
$$P = \sum_{t=1}^{n} \frac{C}{(1+y)^t} + \frac{F}{(1+y)^n}$$
Where:
- P = current market price
- C = coupon payment per period
- F = face value
- n = number of periods to maturity
- y = yield per period (YTM ÷ payments per year)
Practical shortcut: Use the YIELD function in Excel:
=YIELD(settlement, maturity, rate, price, redemption, frequency)
Most bond-related comparison tools and broker platforms display YTM directly — you rarely need to calculate it manually.
Current Yield vs YTM
Current yield = Annual coupon ÷ Current price
This simpler measure ignores the capital gain or loss from buying at a discount or premium to face value.
Example comparison:
- Bond price: $920 (below $1,000 face value)
- Annual coupon: $40 (4% coupon rate)
- Current yield: $40 ÷ $920 = 4.35%
- YTM: ~5.05% (includes the $80 capital gain at maturity spread over remaining years)
YTM gives the more accurate total return picture. Current yield is a simpler estimate.
YTM and Bond Pricing — The Key Relationship
| Market rate moves | Bond price | YTM |
|---|---|---|
| Rises | Falls | Rises |
| Falls | Rises | Falls |
| Unchanged | Unchanged | Unchanged |
Bond prices and yields always move in opposite directions. When you see that a bond is “trading at a premium” (above face value), its YTM is below its coupon rate. “Trading at a discount” means YTM exceeds the coupon rate.
Using YTM to Compare Bonds
YTM is the standard comparison metric for bonds:
- Compare bond A (YTM 4.80%) vs bond B (YTM 5.10%) — bond B offers higher return
- Compare a bond (YTM 5.00%) vs a term deposit (5.20%) — term deposit is slightly higher, but the bond may be more liquid
- Compare a corporate bond (YTM 5.50%) vs a government bond (YTM 4.50%) — the 1.00% spread is the credit premium; decide if the credit risk of the corporate is worth it
YTM Limitations
YTM assumes:
- You hold the bond to maturity (not selling before)
- All coupons are reinvested at the same YTM rate (rarely exactly true)
- The issuer does not default (important for corporate bonds)
For bonds sold before maturity, actual return depends on the price at the time of sale — which can differ significantly from YTM.
Checking YTM on Australian Bonds
For ASX-listed Treasury Bonds: the AOFM website (aofm.gov.au) and major broker platforms display current YTMs.
For bond ETFs: YTM of the underlying portfolio is typically disclosed in the fund’s factsheet (look for “weighted average YTM” or “portfolio yield”).
Related Articles
- Bond Duration Explained Australia
- Australian Government Bonds Explained
- Bond ETFs vs Direct Bonds Australia
- Corporate Bonds Australia
- Bonds hub
Frequently Asked Questions
What is a good yield to maturity for Australian bonds in 2026? YTM benchmarks against the RBA cash rate and term deposit rates. In 2026, Australian government bond YTMs reflect the prevailing rate environment — check the AOFM website for current figures. Corporate bonds typically offer 0.5–2.5% above government bond YTMs depending on credit rating.
Is YTM the same as the interest rate on a bond? No. The coupon rate (interest rate) is fixed at issue based on face value. YTM is the effective return calculated from the current market price — it changes daily as bond prices move. For a bond purchased at face value, the YTM equals the coupon rate. At any other price, they differ.
Does a higher YTM always mean a better investment? Not necessarily — higher YTM typically reflects higher risk (longer duration, lower credit quality, or both). A corporate bond with a 7% YTM carries substantially more default risk than a government bond at 4.5%. Compare YTM within similar credit quality and duration — not across fundamentally different bond types.
This article provides general financial information only. For advice tailored to your situation, speak with a licensed financial adviser through the ASIC financial advisers register or MoneySmart.