Buying a car on finance means committing to a regular repayment for anywhere from one to seven years. Before you sign anything, it makes sense to know exactly what that repayment will look like and how much the loan will cost you in total. The good news is that calculating car loan repayments is straightforward once you understand the four variables that drive the number.
This guide walks through how repayments are calculated, what changes them, and how to use the Avara Finance repayment calculator to map out your budget before you apply.
Key Takeaways
- Car loan repayments are based on your loan amount, interest rate, loan term, and repayment frequency.
- A larger loan amount means higher repayments and more interest paid over time.
- Lower interest rates can significantly reduce both your regular repayments and the total cost of your loan.
- Choosing a shorter loan term usually means higher repayments but less interest overall, while a longer term lowers repayments but increases the total interest paid.
- Making weekly or fortnightly repayments may help reduce the total interest you pay compared to monthly repayments.
- Most Australian car loans have fixed interest rates, giving you consistent repayments throughout the loan term.
- A comparison rate provides a better indication of the overall cost of a loan because it includes most standard fees and charges.
- A balloon payment can lower your regular repayments but leaves a lump sum to pay at the end of the loan.
- A repayment calculator is a useful way to compare different loan scenarios before applying, but it provides estimates only.
- Comparing loan options from multiple lenders can help you find a finance solution that best suits your budget and borrowing needs.
How Car Loan Repayments Are Calculated
Every car loan repayment covers two things:
- a portion of the principal (the amount you borrowed)
- and a portion of the interest (what the lender charges for providing the money). At the start of the loan, most of each payment goes toward interest.
As the balance reduces, more of each payment chips away at the principal. The repayment amount itself stays the same throughout; what changes is the split underneath.
r = Your interest rate per payment period. (To find this, divide the annual interest rate by 12.
n = The total number of payments over the life of the loan.
How lenders calculate interest on a car loan
Most lenders calculate car loan interest daily, based on the outstanding balance at the time. The annual interest rate is divided by 365 to get a daily rate, then multiplied by the current balance to give a daily interest charge. Those daily amounts are added up across the month and charged as a single monthly interest figure.
For example, on a $30,000 loan at 8% per annum, the daily interest in the first month works out to roughly $6.58. Over a 30-day month, that adds up to about $197 in interest for that period. By month 36 of the same loan, the balance has reduced enough that the monthly interest charge is closer to $90. Your repayment amount stays fixed. The principal portion just gets larger as the interest portion shrinks.
This structure is called an amortising loan, and it is standard for car finance in Australia.
Learn More: What Is Vehicle Finance?
The Four Variables That Change Your Repayments
1. Loan amount (the principal)
This is the amount you actually borrow, not the purchase price of the car. If you put down a deposit or trade in an existing vehicle, that amount gets subtracted from the purchase price before the loan is calculated. A $35,000 car with a $5,000 deposit means a $30,000 loan. Lower principal means lower repayments and less total interest paid. It is worth running both scenarios through a calculator to see the actual dollar difference before deciding on a deposit size.
2. Interest rate
Your interest rate is set by the lender based on several factors: your credit history, employment status, loan size, the age of the vehicle, and whether the loan is secured or unsecured. A secured car loan, where the vehicle acts as collateral, typically attracts a lower rate than an unsecured personal loan for the same amount. Current car loan rates in Australia generally start from around 6% for well-qualified borrowers, with the average personal lending rate sitting around 10% according to recent Reserve Bank of Australia data. The rate you are offered can vary significantly between lenders, which is one reason comparing multiple options before applying is worth the effort.
3. Loan term
The loan term is how long you have to repay the loan, typically between one and seven years in Australia. A shorter term means higher repayments, but you pay less interest overall. A longer term means lower repayments but more interest over the life of the loan.
The table below shows how the same $30,000 loan at 8.5% p.a. plays out across different terms. Figures are estimates based on monthly repayments and exclude fees and charges.
Loan term comparison (illustrative only, $30,000 at 8.5% p.a.)
| Loan Term | Estimated Monthly Repayment | Total Interest Paid |
| 3 years | Around $949 per month | Around $4,164 |
| 5 years | Around $616 per month | Around $6,960 |
| 7 years | Around $474 per month | Around $9,816 |
| Loan Term | Estimated Monthly Repayment | Total Interest Paid |
Note: These figures are illustrative estimates only and do not include establishment fees, account-keeping fees, or other lender charges. Actual repayments will vary based on your rate and loan terms.
The choice between a short and long term often comes down to what you can comfortably manage each month versus how much total interest you are prepared to pay. A five-year term is one of the most common choices among Australian car buyers.
4. Repayment frequency
Most lenders let you choose between weekly, fortnightly, or monthly repayments. Matching your repayment frequency to your pay cycle is the practical reason most people choose one over another. But frequency can also make a small difference to the total interest you pay.
Paying fortnightly rather than monthly means you end up making 26 half-payments per year, which is equivalent to 13 monthly payments instead of 12. That extra payment each year reduces the outstanding balance faster, which cuts the interest charged over the life of the loan. The saving is not enormous on a car loan, but on a five-year term it can amount to a few hundred dollars.
Fixed vs Variable Interest Rates on Car Loans
The vast majority of car loans in Australia come with a fixed interest rate. This means the rate is locked in at the start and stays the same for the entire loan term, so your repayment amount never changes. Fixed rates make budgeting more straightforward because you know exactly what is coming out of your account each month.
Variable-rate car loans do exist, but are less common. With a variable rate, the lender can adjust the rate in response to changes in the market or the RBA cash rate. This means your repayments can go up or down. Some borrowers prefer a variable rate for the flexibility it can offer, such as the ability to make extra repayments or pay the loan off early without a break fee. But others prefer the certainty of fixed.
What is a comparison rate, and why does it matter?
A comparison rate gives you a clearer picture of the overall cost of a car loan. It combines the advertised interest rate with most standard fees and charges, so you can compare loan options more accurately.
While a loan with a lower advertised interest rate may seem like the cheapest option, additional fees can make it more expensive than a loan with a slightly higher interest rate but fewer charges.
When comparing car loans, look at the comparison rate as well as the interest rate. It provides a better indication of what the loan is likely to cost overall, helping you make a more informed decision.
What Is a Balloon Payment on a Car Loan?
A balloon payment is a large lump sum that you agree to pay at the end of the loan term instead of building it into your regular repayments. By deferring a portion of the principal to the end, the lender calculates your monthly repayments on a smaller balance, which brings the instalment amount down.
For example, on a $30,000 loan over five years with a 20% balloon, you would be repaying $24,000 across the term and owing $6,000 at the end. The regular repayments are lower, but the $6,000 is due as a lump sum on the final payment date. At that point, most borrowers either pay it from savings, refinance it into a new loan, or use the trade-in value of the car to cover it.
Balloon payments suit buyers who want lower regular repayments during the loan term and are confident they can manage the final lump sum, whether through savings, a trade-in, or a refinance. They are not suitable for everyone. If you are not sure how you would handle the balloon at the end, a standard loan with no balloon is generally the more straightforward choice.
The Avara Finance repayment calculator includes a balloon payment option so you can model both scenarios side by side before deciding.
How to Use the Avara Finance Car Loan Calculator
The Avara Finance calculator is free to use and gives you an instant repayment estimate based on the inputs you enter. Here is how to get the most out of it.
Step 1: Enter your loan amount
Start with the amount you plan to borrow. If you are putting down a deposit or trading in a vehicle, subtract that from the car’s purchase price to get your actual loan amount. Do not include registration, stamp duty, or dealer delivery fees unless you are rolling those costs into the loan.
Step 2: Choose your loan term
The calculator lets you select between one and seven years. Try a few different terms to see how the repayment changes. If the difference between a five-year and a seven-year repayment is small in dollar terms but the total interest saving is significant, a shorter term is often worth it.
Step 3: Enter an interest rate
If you already have a rate from a lender, enter that. If not, use a benchmark rate between 7% and 10% to get a realistic working estimate. Once Avara Finance assesses your application, we can give you a more accurate rate based on your actual profile and the lenders available to you.
Step 4: Set a balloon amount (optional)
If you want to model the impact of a balloon payment, select a percentage from the dropdown. The calculator will show you the lower regular repayment alongside the lump sum that would be due at the end of the term.
Step 5: Select repayment frequency
Choose weekly, fortnightly, or monthly depending on how you want to pay. The result updates instantly.
The result is an estimate. It does not factor in establishment fees, ongoing fees, or any charges specific to a particular lender. When you are ready to see real figures from actual lenders, Avara Finance compares 40-plus options to find the most competitive rates available to you.
Plan Your Budget with the Avara Finance Repayment Calculator
What the Calculator Does Not Tell You
A repayment calculator is a planning tool. It gives you a reliable estimate based on the numbers you enter, but it does not include lender fees, and the rate it uses may differ from the rate you are actually offered once your application is assessed.
What it does very well is help you compare scenarios. Run the same loan amount through a three-year and a five-year term. See how much a 1% difference in rate changes your monthly payment. Test whether a 10% deposit meaningfully reduces your repayments or whether you are better off keeping that cash for running costs.
Once you have a number you are comfortable with, the next step is speaking with a broker. Avara Finance assesses your profile against 40-plus lenders and comes back with options that reflect your actual borrowing situation, not a generic benchmark. Approvals can come through within hours of a complete application.
Final Word
Calculating your car loan repayments before you apply is one of the easiest ways to make a more informed financial decision. By understanding how your loan amount, interest rate, loan term, repayment frequency, and any balloon payment affect your repayments, you can choose a loan that fits both your budget today as well as your long-term financial goals.
However, it is important to remember that while repayment calculators provide a helpful estimate, the actual cost of your loan will depend on the lender, your financial circumstances, and any applicable fees. That’s why it’s important to compare your options rather than focusing on the advertised interest rate alone.
At Avara Finance, we make that process simple. Our free repayment calculator helps you explore different loan scenarios in minutes, and when you’re ready to apply, we’ll compare offers from more than 30 lenders to help you find a competitive car loan that suits your needs.
