---
title: Mortgage Repayments by Loan Amount Table | GNT Finance
description: Monthly principal and interest repayments on $300,000 to $1,000,000 home loans at illustrative rates of 5.00% to 7.00%, over 30 and 25 years, with totals.
url: https://gntfinance.com.au/guides/repayments-by-loan-amount/
section: guides
updated: 2026-09-02
author: Gorakh Timilsina, GNT Finance
---

# Mortgage repayments by loan amount

**In short:** On a 30 year principal and interest loan at 6.00% p.a., $500,000 costs about $2,998 a month, $600,000 about $3,597 and $800,000 about $4,796. As a rule of thumb at that rate, every $100,000 borrowed costs roughly $600 a month. Every 0.50 percentage point of rate adds about $32 a month per $100,000 borrowed.

The tables below are reference points, not quotes. **The rates shown are illustrative round numbers used to make the arithmetic comparable — they are not rates we offer, and no rate is being advertised here.** Your actual repayment depends on the rate you are approved for, your term, your repayment frequency and whether the loan is principal and interest or interest only. Every figure here is calculated with the same engine that powers our [mortgage repayment calculator](/calculators/mortgage-repayment/), so the page and the calculator agree to the dollar.

## Monthly repayments over 30 years

Principal and interest, monthly repayments, rounded to the nearest dollar.

| Loan amount | 5.00% | 5.50% | 6.00% | 6.50% | 7.00% |
|---|---|---|---|---|---|
| $300,000 | $1,610 | $1,703 | $1,799 | $1,896 | $1,996 |
| $400,000 | $2,147 | $2,271 | $2,398 | $2,528 | $2,661 |
| $500,000 | $2,684 | $2,839 | $2,998 | $3,160 | $3,327 |
| $600,000 | $3,221 | $3,407 | $3,597 | $3,792 | $3,992 |
| $700,000 | $3,758 | $3,975 | $4,197 | $4,424 | $4,657 |
| $800,000 | $4,295 | $4,542 | $4,796 | $5,057 | $5,322 |
| $900,000 | $4,831 | $5,110 | $5,396 | $5,689 | $5,988 |
| $1,000,000 | $5,368 | $5,678 | $5,996 | $6,321 | $6,653 |

### How to read this table

- **Linear in the loan amount.** At 6.00%, $300,000 costs $1,799 and $600,000 costs $3,597, almost exactly double, so you can interpolate: $650,000 at 6.00% is about $3,897.
- **Not linear in the rate.** Moving from 5.00% to 7.00% on $600,000 adds $771 a month, 24% more payment for a 40% higher rate. Interest is charged on a declining balance, so the payment rises more slowly than the rate.
- **Each 0.50 percentage point costs about $32 a month per $100,000.** On $500,000 that is roughly $162 a month per half-point.

## Monthly repayments over 25 years at 6.00%

A shorter term raises the monthly payment and cuts the total interest sharply.

| Loan amount | 30 years at 6.00% | 25 years at 6.00% | Extra per month |
|---|---|---|---|
| $300,000 | $1,799 | $1,933 | $134 |
| $400,000 | $2,398 | $2,577 | $179 |
| $500,000 | $2,998 | $3,222 | $224 |
| $600,000 | $3,597 | $3,866 | $269 |
| $700,000 | $4,197 | $4,510 | $313 |
| $800,000 | $4,796 | $5,154 | $358 |
| $900,000 | $5,396 | $5,799 | $403 |
| $1,000,000 | $5,996 | $6,443 | $447 |

Five fewer years costs about 7.5% more each month, and it is the cheapest interest saving available to most borrowers.

## Worked example: the full cost of a $600,000 loan

Take a $600,000 loan, for illustration at 6.00% p.a., principal and interest over 30 years.

**The repayment**

- Monthly repayment: **$3,597**
- Number of payments: 30 × 12 = **360**
- Total repaid: $3,597.30 × 360 = **$1,295,029**
- Total interest: $1,295,029 − $600,000 = **$695,029**

Over the full term you repay more in interest than you borrowed. That is normal on a 30 year loan at this rate, and it is what makes the case for paying extra.

**What an extra $200 a month does**

Keep everything the same and pay $3,797 a month instead of $3,597.

| | Minimum repayments | Plus $200 a month |
|---|---|---|
| Monthly payment | $3,597 | $3,797 |
| Months to repay | 360 | 313 |
| Time to repay | 30 years | 26 years 1 month |
| Total interest | $695,029 | $588,336 |

- Interest saved: $695,029 − $588,336 = **$106,693**
- Time saved: 360 − 313 = **47 months**, or 3 years and 11 months
- Total extra paid: $200 × 313 = **$62,600**

You spend $62,600 to save $106,693 and finish nearly four years early. Every extra dollar works at your loan's interest rate, tax-free, and on most variable loans you can pull it back out through redraw. Model it in the [extra repayments calculator](/calculators/extra-repayments/), or test a windfall in the [lump sum calculator](/calculators/lump-sum/).

## What changes these numbers

### Repayment frequency

Paying half the monthly amount every fortnight means 26 payments a year rather than 24 half-payments: one extra monthly repayment a year, shortening the loan by several years for no change to your budget beyond timing. Compare the options in the [repayment frequency calculator](/calculators/repayment-frequency/).

### Interest only

An interest-only loan at 6.00% on $600,000 costs $3,000 a month rather than $3,597, because you are paying interest and nothing else. The balance does not move, and at the end of the interest-only period the repayment jumps because the same principal must be repaid over a shorter remaining term. Read [interest-only loans explained](/guides/interest-only-loans-explained/).

### An offset account

Money in a full offset account reduces the balance interest is calculated on without reducing the balance owing. $40,000 sitting in offset against a $600,000 loan at 6.00% saves roughly $2,400 of interest a year, while remaining available. Read [offset vs redraw](/guides/offset-vs-redraw/).

### Fees and the comparison rate

The repayment in the tables is calculated on the interest rate alone. Annual package fees, monthly account fees and upfront costs are not in it. The comparison rate exists to fold most of those into a single number, and it is the right figure for comparing two loans. See [comparison rate explained](/guides/comparison-rate-explained/).

### Fixed versus variable

A fixed rate holds the repayment steady for the fixed term and then reverts. A variable repayment moves with the rate. If you are trying to work out which suits you, read [fixed vs variable rate](/guides/fixed-vs-variable-rate/).

## Working backwards: from a repayment to a loan size

If you know what you can comfortably pay each month, the tables run in reverse. At 6.00% over 30 years:

| Comfortable monthly repayment | Approximate loan supported |
|---|---|
| $1,800 | $300,000 |
| $2,400 | $400,000 |
| $3,000 | $500,000 |
| $3,600 | $600,000 |
| $4,200 | $700,000 |
| $4,800 | $800,000 |

Two warnings about using this as a borrowing target. First, a lender will not assess you at 6.00%: under the APRA serviceability buffer every lender assesses at your rate **plus 3 percentage points**, so a loan priced at 6.00% is tested at 9.00%, where $600,000 costs $4,828 a month. The [borrowing power calculator](/calculators/borrowing-power/) applies the buffer for you.

Second, the repayment is not the whole cost of the property. Rates, water, insurance, owners corporation fees and maintenance sit on top, and lenders count them. To lift the number, read [how to improve borrowing power](/guides/how-to-improve-borrowing-power/).

## A note on what these tables are and are not

- They assume principal and interest, a constant rate for the full term, and monthly payments made on time.
- They exclude lenders mortgage insurance, which applies above 80% LVR and is usually added to the loan. See [understanding LVR and LMI](/guides/understanding-lvr-and-lmi/).
- They exclude fees, offset balances, redraw and any rate change during the term.
- The rates are illustrative reference points chosen so the arithmetic is easy to compare. Not a rate offer, not a market average, not a prediction.

If you already have a loan and the repayment in these tables is lower than what you pay on the same balance, that is worth a conversation. Read the [refinancing guide](/guides/refinancing-guide/).

## Frequently asked questions

### What are the repayments on a $500,000 mortgage?

On a 30 year principal and interest loan, for illustration: about $2,684 a month at 5.00% p.a., $2,998 at 6.00% and $3,327 at 7.00%. Over 25 years at 6.00% it is about $3,222 a month. These figures exclude fees, lenders mortgage insurance and rate changes, and are illustrative reference points rather than a rate offer.

### What are the repayments on a $600,000 mortgage over 30 years?

About $3,597 a month, for illustration at 6.00% p.a., principal and interest. Over the full 30 years that is $1,295,029 repaid in total, of which $695,029 is interest. At 5.00% the repayment would be $3,221 a month and at 7.00% it would be $3,992, so a two percentage point difference in rate is $771 a month.

### How much difference does one percentage point make?

More than most people expect over a full term, and less than expected month to month. On $600,000 over 30 years, moving from 6.00% to 7.00% adds $395 a month. As a general rule at these levels, each 0.50 percentage point adds about $32 a month for every $100,000 borrowed, so on $400,000 a half-point costs about $130 a month.

### Is it better to pay extra or shorten the loan term?

They achieve almost the same thing, but paying extra on a longer term keeps your minimum repayment low, which is safer if your income changes. On a $600,000 loan at 6.00%, an extra $200 a month clears the loan in 26 years and one month and saves $106,693 in interest, while your contractual minimum stays at $3,597. Check whether extra repayments and redraw are allowed on your loan first.

### What rate will a lender actually assess me at?

Your rate plus 3 percentage points, under the APRA serviceability buffer. A loan priced at 6.00% is tested at 9.00%, which on $600,000 over 30 years is $4,828 a month rather than $3,597. The buffer applies to existing debts too, so credit card limits, car loans and an existing mortgage are all assessed at buffered rates when you apply for something new.

### Do these repayments include fees and insurance?

No. The tables calculate principal and interest on the interest rate alone. Annual package fees, monthly account fees, lenders mortgage insurance above 80% LVR, rates, water, building insurance and owners corporation fees all sit on top. Use the comparison rate when comparing two loans, because it folds most of the lender's own fees into a single figure.

## Talk to GNT Finance

These tables tell you what a loan costs. They cannot tell you which loan you will be approved for, at what rate, or how the structure should be set up. That takes a conversation about your income, your deposit and your plans. Gorakh Timilsina assessed loan applications as a senior credit officer before founding GNT Finance, so the numbers you get from us are the ones a lender will work to.

[Book a free consultation](/contact/) or call 0426 403 703.