A mortgage is a loan secured against property, typically used to purchase a home. In New Zealand, mortgages are one of the most significant financial commitments most people will make, usually repaid over 25-30 years.
When you take out a mortgage, you're entering into an agreement with a lender (usually a bank) where:
The amount you borrow. If you buy a $600,000 house with a $120,000 deposit, your principal is $480,000. As you make repayments, the principal reduces.
The cost of borrowing money, expressed as an annual percentage rate. For example, a 7% interest rate on a $500,000 loan means you'll pay approximately $35,000 in interest in the first year (though this decreases as the principal reduces).
The portion of the property you actually own. Equity = Property Value - Loan Balance. If your $600,000 property has a $480,000 mortgage, you have $120,000 equity (20%).
The loan amount as a percentage of the property's value. An 80% LVR means you're borrowing 80% and have a 20% deposit.
The process of gradually paying off your loan over time. Each payment includes both interest and principal. Early payments are mostly interest; later payments are mostly principal.
The amount you need for a deposit depends on several factors:
The Reserve Bank of New Zealand (RBNZ) sets limits on how much banks can lend at high LVRs. These rules change periodically based on economic conditions. Currently, banks can only lend to a small percentage of borrowers with LVRs above 80%.
The standard mortgage type in New Zealand. Each repayment covers both interest and some principal.
You pay only the interest for an agreed period (typically 1-5 years). The principal remains unchanged.
While interest-only mortgages offer lower initial payments, you're not building equity through repayments. You'll rely entirely on property appreciation for equity growth. When the interest-only period ends, payments jump significantly.
A mortgage that works like a large overdraft facility. Your salary goes in, expenses come out, and interest is calculated daily on the balance.
Your savings account is linked to your mortgage. The savings balance reduces the amount you're charged interest on.
Getting pre-approval shows sellers you're a serious buyer with financing secured. This can strengthen your offer, especially in competitive markets. Pre-approval usually takes 1-3 days and requires proof of income, expenses, debts, and savings.
Understanding how mortgage interest works and choosing the right rate structure is crucial to minimizing the total cost of your home loan.
| Feature | Fixed Rate | Floating Rate |
|---|---|---|
| Interest Rate | Locked for set period (6 months to 5 years) | Changes with market conditions |
| Repayment Amount | Fixed and predictable | Varies as rate changes |
| Current NZ Rates (2025) | 6.5% - 7.5% | 8.5% - 9.0% |
| Extra Repayments | Limited (usually $30k/year max) | Unlimited, no penalty |
| Break Fees | Yes, can be substantial | None |
| Best For | Budgeting certainty, rate protection | Flexibility, repayment freedom |
Interest is calculated daily on your outstanding loan balance, then charged at your payment frequency (usually fortnightly or monthly).
Every dollar you pay off principal saves you $0.07 per year in interest (at 7%). Pay off $10,000 extra principal, save $700 per year in interest. This compounds significantly over the life of your loan.
You can usually choose to pay weekly, fortnightly, or monthly. The frequency affects how much you pay overall.
| Frequency | Payment Amount | Payments/Year | Annual Total | Total Paid |
|---|---|---|---|---|
| Monthly | $3,327 | 12 | $39,924 | $1,197,720 |
| Fortnightly | $1,534 | 26 | $39,884 | $1,174,080 |
| Weekly | $767 | 52 | $39,884 | $1,174,080 |
Amortization is how your loan is gradually paid off. Each payment includes both interest and principal, but the split changes over time.
| Month | Payment | Interest | Principal | Balance |
|---|---|---|---|---|
| 1 | $3,327 | $2,917 | $410 | $499,590 |
| 6 | $3,327 | $2,903 | $424 | $497,512 |
| 12 | $3,327 | $2,888 | $439 | $495,341 |
| Month | Payment | Interest | Principal | Balance |
|---|---|---|---|---|
| 354 | $3,327 | $213 | $3,114 | $33,413 |
| 359 | $3,327 | $116 | $3,211 | $16,647 |
| 360 | $3,327 | $19 | $3,308 | $0 |
Notice: In month 1, only $410 goes to principal (12% of payment). By month 360, $3,308 goes to principal (99% of payment).
In New Zealand, you can typically fix your rate for:
| Term | Typical Rate | When to Choose |
|---|---|---|
| 6 months | 6.5% - 7.0% | Expect rates to fall soon |
| 1 year | 6.7% - 7.2% | Most popular; balance of rate and flexibility |
| 2 years | 6.5% - 7.0% | Medium-term certainty |
| 3 years | 6.9% - 7.4% | Longer-term stability |
| 5 years | 7.2% - 7.7% | Maximum certainty, expect rates to rise |
If you pay off or refinance a fixed-rate mortgage early, you'll likely pay a break fee. This can range from a few hundred to tens of thousands of dollars, depending on how much rates have moved since you fixed.
Even small extra payments can dramatically reduce your loan term and total interest paid.
| Scenario | Monthly Payment | Total Paid | Loan Term | Interest Saved |
|---|---|---|---|---|
| Standard | $3,327 | $1,197,720 | 30 years | - |
| +$100/month | $3,427 | $1,129,248 | 27.5 years | $68,472 |
| +$200/month | $3,527 | $1,078,680 | 25.5 years | $119,040 |
| +$500/month | $3,827 | $976,404 | 21.3 years | $221,316 |
The right mortgage strategy depends on your financial situation, risk tolerance, and future plans. Let's explore how to make these important decisions.
Many experts recommend splitting your mortgage across different fixed terms and floating rates. This balances security with flexibility.
| Portion | Amount | Type | Rate | Purpose |
|---|---|---|---|---|
| 50% | $300,000 | Fixed 1-year | 6.8% | Medium-term stability |
| 30% | $180,000 | Fixed 2-year | 6.5% | Longer-term certainty |
| 20% | $120,000 | Floating | 8.5% | Flexibility for extra payments |
As each fixed portion expires, reassess rates and fix again (or leave floating). This creates a "rolling" structure where you regularly review 1/3 to 1/2 of your mortgage, maintaining flexibility while keeping some stability.
| Term | Monthly Payment | Total Paid | Total Interest |
|---|---|---|---|
| 30 years | $3,327 | $1,197,720 | $697,720 |
| 25 years | $3,536 | $1,060,800 | $560,800 |
| 20 years | $3,876 | $930,240 | $430,240 |
| 15 years | $4,494 | $808,920 | $308,920 |
Understanding how rate changes affect your repayments helps you plan for worst-case scenarios.
| Interest Rate | Monthly Payment | Total Paid | vs 7% |
|---|---|---|---|
| 6% | $2,998 | $1,079,280 | -$329/month |
| 7% | $3,327 | $1,197,720 | baseline |
| 8% | $3,669 | $1,320,840 | +$342/month |
| 9% | $4,023 | $1,448,280 | +$696/month |
A 2% rate increase from 7% to 9% adds $696 to monthly repayments on a $500,000 mortgage. Before borrowing, ensure you can afford payments if rates rise by 2-3%. This is called "stress testing" your mortgage.
Refinancing means moving your mortgage to a new lender (or renegotiating with current lender). Consider refinancing when:
| Factor | First Home | Investment Property |
|---|---|---|
| Minimum Deposit | 5-20% (with FHL or low equity) | 30% minimum (40% for new rules) |
| Interest Rates | Standard rates | Usually 0.25-0.5% higher |
| Tax Deductibility | No interest deductibility | Limited/no deductibility on residential |
| Mortgage Type | Usually table mortgage | Often interest-only initially |
| Primary Goal | Pay off quickly, build equity | Cashflow management, tax efficiency |
Let's look at practical mortgage scenarios showing different strategies and situations.
Situation: Young professional couple buying their first home in Auckland. Combined household income $140,000.
They decided to split their mortgage:
| Portion | Type | Rate | Monthly Payment |
|---|---|---|---|
| $400,000 | Fixed 1-year | 6.8% | $2,620 |
| $200,000 | Fixed 2-year | 6.5% | $1,284 |
| Total | $3,904 |
Situation: Mike owns his own home and is buying his first investment property. Income $95,000.
Mike chose interest-only for 5 years at 7.2%
Mike chose interest-only to maximize cashflow in early years. He's betting on property appreciation rather than equity build-up through repayments. After 5 years, if the property value increases to $650,000, his equity grows from $165k to $265k despite not paying down principal.
Situation: Jennifer's 2-year fixed rate is expiring. Her mortgage has reduced from $450,000 to $420,000. Property now valued at $850,000.
Situation: Young professionals wanting to be mortgage-free as soon as possible. Both 32 years old, combined income $165,000.
David & Lisa decided to pay $4,000/month (extra $806)
Situation: Robert's mortgage is coming off a fixed term. He's evaluating different rate structures for his $380,000 mortgage.
Robert's split strategy costs slightly more than going all fixed 3-year ($166/month or $40/week), but gives him significantly more flexibility and shorter commitments. If rates drop by 1%, his floating portion saves him $1,583/year, making the split strategy better than all-fixed.
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