When I first started learning about investing, I kept coming across bonds. I assumed they were just a safer type of share – something you bought on the same market, just with lower risk and lower returns.
Turns out, I had it completely wrong.
Bonds aren’t a type of share at all. They’re a completely different asset class, traded on a different market, and they play a very different role in your portfolio.
Shares vs Bonds: Different Markets, Different Roles
When you buy a share:
- You buy it on the share market (NZX)
- You become a part-owner of a company
- You’re buying equity
When you buy a bond:
- You buy it on the NZX Debt Market (NZDX) – part of the NZX, but focused on bonds rather than shares
- You become a lender, not an owner
- You’re buying debt
These are fundamentally different decisions.
You’re not choosing between “risky shares” and “safe shares”. You’re choosing between owning businesses and lending money to them.
How Bonds Actually Work
When an entity needs to raise money – the NZ Government, Auckland Council, Contact Energy – it can borrow from a bank or issue bonds to investors.
Those investors are effectively lending money in exchange for interest.
Example: You buy a $1,000 Auckland Council bond with a 5-year term paying 5% interest.
- You lend Auckland Council $1,000
- They pay you 5% interest each year (the coupon rate)
- After five years, they repay your $1,000
- This is a legally binding loan agreement
You haven’t bought a piece of Auckland Council. You’re a creditor – someone they owe money to.
(In practice, many council or corporate bonds are accessed via managed funds rather than bought directly by retail investors.)
Why Bonds Usually Pay Less Than Shares
Bond returns are lower because bonds are more predictable.
When you hold a quality bond to maturity, you know exactly what you’ll get: your principal back plus your agreed interest.
With shares, outcomes are far less certain. Profits fluctuate, valuations swing, and companies can fail entirely.
There’s also an important hierarchy here: bondholders get paid before shareholders if something goes wrong. That priority reduces risk – and lower risk means lower expected returns.
Classic risk–return trade-off.
Bonds are generally less volatile than shares, but they’re not risk-free, and their prices do still move.
Not All Bonds Are Equal
All bonds are debt – but not all debt is equally safe.
Government bonds (e.g. NZ Government): very low risk, lower interest Council or large corporate bonds (e.g. Auckland Airport, Contact Energy): moderate risk, moderate interest
Riskier issuers: higher risk, higher interest (to attract lenders)
This is reflected in credit ratings, which assess how likely the borrower is to repay you.
A government bond paying 3% might look dull next to a startup offering 8% – but that higher return exists because there’s a real chance the startup won’t pay you back.
Bond Prices Change Too
You can sell bonds before maturity on the debt market, and their prices fluctuate based on the broader lending environment.
Interest rates matter for all lending – whether it’s the bank paying you interest on savings, charging interest on mortgages, or entities paying interest on bonds. These rates move together based on the economic environment (heavily influenced by the Reserve Bank’s OCR).
Example: Say I buy a bond paying 5% when the general interest rate environment is around 4-5%.
Then the Reserve Bank raises the OCR to control inflation, and interest rates across the economy rise:
- New bonds now pay 6%: My bond paying 5% is less attractive. If I want to sell it before maturity, I’ll get less than I paid for it.
Or the Reserve Bank drops the OCR, and interest rates fall:
- New bonds only pay 3%: My bond paying 5% is suddenly very attractive. Its market value increases.
The bond’s coupon rate is locked in – that doesn’t change. What changes is how much someone will pay to buy your bond before it matures, based on what new bonds are paying.
Important: If you hold a bond to maturity, you still receive your agreed interest and your principal back. Losses only occur if you sell early after rates have risen.
How Most Kiwis Actually Invest in Bonds
Although bonds are listed on the NZDX, buying individual bonds directly is uncommon for most people.
Instead, bond exposure usually comes via:
- Managed bond funds (e.g. Simplicity’s International Bond Fund), which hold many bonds across issuers and countries
- KiwiSaver funds, especially Conservative and Balanced options, where bond selection is handled for you
Why This Matters
When you choose a Conservative or Balanced KiwiSaver fund, you’re not just choosing a vague “risk level”.
You’re choosing your mix of:
- Equity (shares) – ownership, higher long-term growth, more volatility
- Debt (bonds) – lending, lower volatility, lower expected returns
When overseas investors talk about a “60/40 portfolio”, they mean 60% shares and 40% bonds.
Two different asset classes. Two different markets. Two different sources of return.
Understanding that distinction is fundamental to understanding your portfolio – and your comfort with risk.
What’s Next?
Now that you know bonds are debt, not equity, the real question isn’t what are bonds?
It’s when – if ever – do they actually belong in your portfolio?
This article is for educational purposes only ans is not personalised financial advice.