Understanding Money NZ - Notes, Coins and Bank Accounts
💵 Understanding Money - Notes, Coins and Bank Accounts
This guide is designed for younger New Zealanders (roughly years 7 to 10) and anyone who wants a clear explainer of how money actually works. We cover what money is, how NZ notes and coins work, the difference between cash and electronic payments, what banks actually do with the money you deposit, and the simple maths of how interest grows your savings.
What Money Actually Is
Money is not valuable by itself. A $20 note is just a piece of polymer plastic with ink on it. Its value comes from one thing: the agreement that everyone will accept it in exchange for goods and services. In the ancient world, people swapped things directly (a sheep for a bag of wheat). This is called barter, and it worked badly because you needed what the other person had AND they needed what you had at the same time. Money solves that problem by creating a thing everyone agrees to accept.
New Zealand's money is issued by the Reserve Bank of New Zealand. The government guarantees it. When you hand over a $20 note, everyone accepts it because they know they can spend it too. That shared agreement is what gives money its value.
NZ Notes
New Zealand has five banknotes, all made of polymer (plastic). They're waterproof, tough, and hard to counterfeit. Each note features a famous New Zealander on the front and a native bird on the back.
| Note | Colour | Person | Bird |
|---|---|---|---|
| $5 | Orange | Sir Edmund Hillary | Hoiho (yellow-eyed penguin) |
| $10 | Blue | Kate Sheppard | Whio (blue duck) |
| $20 | Green | Queen Elizabeth II | Kārearea (NZ falcon) |
| $50 | Purple | Sir Apirana Ngata | Kōkako |
| $100 | Red | Lord Ernest Rutherford | Mohua (yellowhead) |
NZ Coins
NZ has five coins: 10c, 20c, 50c, $1 and $2. We got rid of 1c and 2c coins in 1990 and 5c coins in 2006. Because of this, cash totals get rounded to the nearest 10 cents (Swedish rounding), while EFTPOS and card payments stay exact to the cent.
Rounding examples: $12.43 rounds DOWN to $12.40 (cash only). $12.47 rounds UP to $12.50. Pay by EFTPOS and you pay exact to the cent. Over time, rounding evens out.
💳 Cash, EFTPOS, Cards and Digital Payments
There are many ways to pay in NZ. They look similar but work differently. Understanding the differences matters because some spend YOUR money and some spend BORROWED money.
| Method | How It Works | Key Feature |
|---|---|---|
| Cash | You hand over notes and coins | Anonymous, immediate, works without power |
| EFTPOS | Card + PIN, money moves instantly from your bank | NZ-only system, usually no fee to shops |
| Debit card (Visa/Mastercard) | Spends your money, works online and overseas | Same account, wider acceptance |
| Contactless (tap) | Hold card near terminal, no PIN under $200 | Fast, uses payWave or PayPass |
| Mobile wallet (Apple/Google Pay) | Card on phone, fingerprint or face unlock | No physical card needed |
| Credit card | Bank lends you money, you repay later | Borrowing, NOT your own money |
The Key Difference to Understand
Debit cards, EFTPOS and mobile wallets spend money you ALREADY have. When the money's gone from your account, the transaction fails. You can't spend more than you've got.
Credit cards spend money the BANK lends you, which you have to pay back later. If you don't pay the full balance each month, the bank charges interest (often 20% or more per year). A $100 restaurant bill on a credit card, paid off over 2 years with minimum payments, could cost you $125 or more.
The "Pain of Paying" Effect
Researchers have shown that people spend more when they pay with cards than with cash. Handing over a physical $20 note feels real; tapping a card feels like nothing happened. The brain registers the loss differently. Many adults use this to their advantage: they use cash for daily spending (where the psychological cost helps them spend less) and cards for big planned purchases (where the convenience matters).
Staying Safe With Digital Payments
- Never share your PIN or online banking password with anyone, including family
- Banks NEVER ask for your password in an email or text - that's always a scam
- Don't click links in banking emails; log in manually via the official app
- If something feels off, phone the bank using the number on the back of your card
- Freeze your card in the app the moment it's lost or stolen - it takes 3 seconds
🏦 How Banks Work and How Interest Grows Your Savings
What Banks Actually Do
Most people think a bank stores your money in a vault. That's only partly true. When you deposit $100, the bank keeps a small portion (about $10) in reserves and lends the rest out to other customers as mortgages and loans. Those borrowers pay the bank about 7% interest. The bank pays you around 3% for letting them use your money. The bank keeps the difference (4%) as profit. This system is called fractional reserve banking.
When you want your $100 back, the bank gives it to you from its reserves or from other depositors' money. This works because not everyone wants their money at the same time.
Is your money safe? Yes. NZ banks are heavily regulated by the Reserve Bank, and since 2024 a new Depositor Compensation Scheme protects up to $100,000 per person per bank if a bank fails. The big NZ banks (ANZ, ASB, BNZ, Kiwibank, Westpac) are considered very stable.
How Interest Works
When the bank pays 3% interest on savings, that means for every $100 in the account, the bank adds $3 after one year. You don't do anything; the bank adds it automatically. In year 2, the bank pays 3% on the NEW balance (including the interest already earned). This is called compound interest.
Long-Term Compounding Numbers
| Years | Balance (at 3% p.a. on $1,000) | Total Interest Earned |
|---|---|---|
| 1 | $1,030 | $30 |
| 5 | $1,159 | $159 |
| 10 | $1,344 | $344 |
| 20 | $1,806 | $806 |
| 30 | $2,427 | $1,427 |
The same $1,000 more than doubles after 30 years without adding anything. This is why starting to save early matters so much. Try our Compound Interest Calculator to experiment.
The Rule of 72 (Quick Mental Maths)
Divide 72 by the interest rate to estimate how long money takes to double:
The rule works for any rate between about 1% and 20%. Small differences in rates compound into huge differences over decades. $1,000 at 3% over 48 years grows to $4,000. The same $1,000 at 6% grows to $16,000. Four times more, just from doubling the rate.
🔢 Worked Examples and Real-World Stories
Example 1: Cash Rounding at the Dairy
Te Aroha buys snacks: Pie $4.80, drink $3.50, chocolate $2.63.
Example 2: Comparing Two Savings Accounts
Jordan has $500 to save. Account A: 2.5% flat, no conditions. Account B: 4.0% IF $20/month deposited AND no withdrawals.
Bonus rates come with conditions. If you can't commit, a lower unconditional rate often wins.
Example 3: Compound Growth - The Power of Starting Early
Maia (14) saves $500 now. Tama (14) waits until 24 to save $500. Both earn 3.5%.
If both also add $20/month: Maia ends with about $33,500, Tama with $23,000. A $10,500 difference, from starting 10 years earlier.
Real-World Story: The $5 That Became $67
Opened her first savings account at age 5.
The Setup:
- Nana added $5 at every birthday and Christmas
- Harper added a dollar or two from pocket money occasionally
After 5 Years:
Lesson: Small amounts consistently added, plus time, plus interest, creates an early understanding of how money grows. The $5 wasn't magic; the habit was.
Real-World Story: The Cashless Day Experiment
A week-long tracking of card-only spending.
What Happened:
Tapping a card doesn't feel like parting with money. No physical reminder of what's left. Small $3 to $5 purchases add up without registering.
Lesson: How you pay affects how much you spend. Knowing this is a superpower.
Real-World Story: The Term Deposit Lesson
Earned $1,200 over summer, locked $1,000 into a 2-year term deposit at 4.5%.
His Decision:
At 17.5, Mason's brother offered him a discounted car, but the money was locked up. He waited. The opportunity passed.
Lesson: Term deposits give higher rates but trade away flexibility. For money you're certain won't be needed, they're great. Flexibility has a real cost.
Real-World Story: When Technology Failed
What Happened:
- Power outages knocked out EFTPOS terminals for days
- Cell towers went down, meaning contactless and banking apps didn't work
- Many ATMs were offline or empty
- The few shops still operating could ONLY take cash
Families with $50 to $200 cash at home managed basic needs. Those without struggled. Since then, Civil Defence recommends NZ households keep a small cash reserve as part of emergency preparedness.
Lesson: The future is cashless for convenience, but cash still has a role in resilience. Having a small cash reserve at home isn't old-fashioned; it's sensible emergency planning.
🎯 Test Your Knowledge
Quiz on Money Basics in NZ