How does the interest rate affect mortgage payments?

How does the interest rate affect mortgage payments?

You’ll usually plan for mortgage repayments in your household budget. If they increase, it may put a strain on your finances. On the other hand, if they are reduced, you can plan how to use the extra money for another purpose. You might ask, why does the mortgage repayment amount fluctuate? It fluctuates because, from time to time, banks change the rate of interest that they charge you depending on overall market trends. 

Your mortgage repayments are made up of two components. The first part is a portion of the principal, and the other is the interest charged on that principal amount. To work out the monthly repayment, your lender will divide the total amount you’ll pay over the life of your loan by the number of months in your loan term. You’ll end up paying almost an equal amount each month. 

If you choose a variable rate home loan, then you may occasionally be told that your monthly repayment has gone up or down as the interest rate has changed. If you choose a fixed rate home loan, on the other hand, you wouldn't have to worry that it will increase until the fixed-rate period expires. But you may lose out on savings if the variable rate drops below what you are paying. 

How does the interest rate affect me?

The interest rate affects the total amount you’ll repay over the life of your home loan. Any fluctuation in the interest rate changes the total amount your home loan will cost you. You should consider this when you’re borrowing, especially if you’re thinking of taking out a variable rate home loan. It's a good idea to think about how you will manage repayments if the interest rate increases. You could consider saving some money to meet this contingency if it arises or making extra mortgage repayments whenever you have funds available. 

A home loan calculator is a very convenient way to see how the interest rate affects mortgage repayments, and it can help you see how any changes will affect the repayments.

Let's assume that you borrow $500,000 at 3 per cent interest for ten years. The total interest you’ll pay works out to over $79,000. Your monthly repayment, which includes both principal and interest, will be a little over $4,800. 

If the interest rate increases to 4 per cent, you would end up paying more than $107,000 in interest over ten years, and your monthly repayment would be over $5,000. On the other hand, if the interest rate reduces to 2 per cent, your total interest cost goes down to about $52,000, and your monthly repayment is about $4,600 only. 

These examples demonstrate that your total interest cost is significant and how a change in interest impacts this amount. It also illustrates that you need to pay attention to changes in the interest rate and its impact on your finances. 

Why do lenders change interest rates?

Lenders borrow funds from other financial institutions at an interest rate termed the cash rate and set by the Reserve Bank of Australia (RBA). Each month, except for January, the RBA decides to increase, decrease or hold the cash rate based on various economic factors. When the cash rate changes, your lender may change your home loan’s interest rate, especially if it’s a variable rate home loan. 

A lender isn’t obligated to change the interest rate on its products every time the cash rate fluctuates. Still, it’s the general expectation and what generally happens. Lenders can also choose to raise or lower the interest rate outside any cash rate changes based on their business objectives. 

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What happens to my home loan when interest rates rise?

If you are on a variable rate home loan, every so often your rate will be subject to increases and decreases. Rate changes are determined by your lender, not the Reserve Bank of Australia, however often when the RBA changes the cash rate, a number of banks will follow suit, at least to some extent. You can use RateCity cash rate to check how the latest interest rate change affected your mortgage interest rate.

When your rate rises, you will be required to pay your bank more each month in mortgage repayments. Similarly, if your interest rate is cut, then your monthly repayments will decrease. Your lender will notify you of what your new repayments will be, although you can do the calculations yourself, and compare other home loan rates using our mortgage calculator.

There is no way of conclusively predicting when interest rates will go up or down on home loans so if you prefer a more stable approach consider opting for a fixed rate loan.

What are the different types of home loan interest rates?

A home loan interest rate is used to calculate how much you’ll pay the lender, usually annually, above the amount you borrow. It’s what the lenders charge you for them lending you money and will impact the total amount you’ll pay over the life of your home loan. 

Having understood what are home loan rates in general, here are the two types you usually have with a home loan:

Fixed rates

These interest rates remain constant for a specific period and are a good option if you’re a first-time buyer or if you’re looking for a fixed monthly repayment. One possible downside of a fixed rate is that it may be higher than a variable rate. Also, you don’t benefit from any lowering of interest rates in the market. On the flip side, if rates go up, your rate won’t change, possibly saving you money.

Variable rates

With variable interest rates, the lender can change them at any time. This change can be based on economic conditions or other reasons. Changes in interest rates could be beneficial if your monthly repayment decreases but can be a problem if it increases. Variable interest rates offer several other benefits often not available with fixed rate home loans like redraw and offset facilities and free extra repayments. 

What is a standard variable rate (SVR)?

The standard variable rate (SVR) is the interest rate a lender applies to their standard home loan. It is a variable interest rate which is normally used as a benchmark from which they price their other variable rate home loan products.

A standard variable rate home loan typically includes most, if not all the features the lender has on offer, such as an offset account, but it often comes with a higher interest rate attached than their most ‘basic’ product on offer (usually referred to as their basic variable rate mortgage).

What is a comparison rate?

The comparison rate is a more inclusive way of comparing home loans that factors in not only on the interest rate but also the majority of upfront and ongoing charges that add to the total cost of a home loan.

The rate is calculated using an industry-wide formula based on a $150,000 loan over a 25-year period and includes things like revert rates after an introductory or fixed rate period, application fees and monthly account keeping fees.

In Australia, all lenders are required by law to publish the comparison rate alongside their advertised rate so people can compare products easily.

What is a variable home loan?

A variable rate home loan is one where the interest rate can and will change over the course of your loan. The rate is determined by your lender, not the Reserve Bank of Australia, so while the cash rate might go down, your bank may decide not to follow suit, although they do broadly follow market conditions. One of the upsides of variable rates is that they are typically more flexible than their fixed rate counterparts which means that a lot of these products will let you make extra repayments and offer features such as offset accounts.

What is the difference between fixed, variable and split rates?

Fixed rate

A fixed rate home loan is a loan where the interest rate is set for a certain amount of time, usually between one and 15 years. The advantage of a fixed rate is that you know exactly how much your repayments will be for the duration of the fixed term. There are some disadvantages to fixing that you need to be aware of. Some products won’t let you make extra repayments, or offer tools such as an offset account to help you reduce your interest, while others will charge a significant break fee if you decide to terminate the loan before the fixed period finishes.

Variable rate

A variable rate home loan is one where the interest rate can and will change over the course of your loan. The rate is determined by your lender, not the Reserve Bank of Australia, so while the cash rate might go down, your bank may decide not to follow suit, although they do broadly follow market conditions. One of the upsides of variable rates is that they are typically more flexible than their fixed rate counterparts which means that a lot of these products will let you make extra repayments and offer features such as offset accounts.

Split rates home loans

A split loan lets you fix a portion of your loan, and leave the remainder on a variable rate so you get a bet each way on fixed and variable rates. A split loan is a good option for someone who wants the peace of mind that regular repayments can provide but still wants to retain some of the additional features variable loans typically provide such as an offset account. Of course, with most things in life, split loans are still a trade-off. If the variable rate goes down, for example, the lower interest rates will only apply to the section that you didn’t fix.

Does the Home Loan Rate Promise apply to discounted interest rate offers, such as honeymoon rates?

No. Temporary discounts to home loan interest rates will expire after a limited time, so they aren’t valid for comparing home loans as part of the Home Loan Rate Promise.

However, if your home loan has been discounted from the lender’s standard rate on a permanent basis, you can check if we can find an even lower rate that could apply to you.

How do I calculate monthly mortgage repayments?

Work out your mortgage repayments using a home loan calculator that takes into account your deposit size, property value and interest rate. This is divided by the loan term you choose (for example, there are 360 months in a 30-year mortgage) to determine the monthly repayments over this time frame.

Over the course of your loan, your monthly repayment amount will be affected by changes to your interest rate, plus any circumstances where you opt to pay interest-only for a period of time, instead of principal and interest.

How can I calculate interest on my home loan?

You can calculate the total interest you will pay over the life of your loan by using a mortgage calculator. The calculator will estimate your repayments based on the amount you want to borrow, the interest rate, the length of your loan, whether you are an owner-occupier or an investor and whether you plan to pay ‘principal and interest’ or ‘interest-only’.

If you are buying a new home, the calculator will also help you work out how much you’ll need to pay in stamp duty and other related costs.

How much are repayments on a $250K mortgage?

The exact repayment amount for a $250,000 mortgage will be determined by several factors including your deposit size, interest rate and the type of loan. It is best to use a mortgage calculator to determine your actual repayment size.

For example, the monthly repayments on a $250,000 loan with a 5 per cent interest rate over 30 years will be $1342. For a loan of $300,000 on the same rate and loan term, the monthly repayments will be $1610 and for a $500,000 loan, the monthly repayments will be $2684.

What is a honeymoon rate and honeymoon period?

Also known as the ‘introductory rate’ or ‘bait rate’, a honeymoon rate is a special low interest rate applied to loans for an initial period to attract more borrowers. The honeymoon period when this lower rate applies usually varies from six months to one year. The rate can be fixed, capped or variable for the first 12 months of the loan. At the end of the term, the loan reverts to the standard variable rate.

What is the best interest rate for a mortgage?

The fastest way to find out what the lowest interest rates on the market are is to use a comparison website.

While a low interest rate is highly preferable, it is not the only factor that will determine whether a particular loan is right for you.

Loans with low interest rates can often include hidden catches, such as high fees or a period of low rates which jumps up after the introductory period has ended.

To work out the best value for money, have a look at a loan’s comparison rate and read the fine print to get across all the fees and charges that you could be theoretically charged over the life of the loan.

What is 'principal and interest'?

‘Principal and interest’ loans are the most common type of home loans on the market. The principal part of the loan is the initial sum lent to the customer and the interest is the money paid on top of this, at the agreed interest rate, until the end of the loan.

By reducing the principal amount, the total of interest charged will also become smaller until eventually the debt is paid off in full.

Why does Westpac charge an early termination fee for home loans?

The Westpac home loan early termination fee or break cost is applicable if you have a fixed rate home loan and repay part of or the whole outstanding amount before the fixed period ends. If you’re switching between products before the fixed period ends, you’ll pay a switching break cost and an administrative fee. 

The Westpac home loan early termination fee may not apply if you repay an amount below the prepayment threshold. The prepayment threshold is the amount Westpac allows you to repay during the fixed period outside your regular repayments.

Westpac charges this fee because when you take out a home loan, the bank borrows the funds with wholesale rates available to banks and lenders. Westpac will then work out your interest rate based on you making regular repayments for a fixed period. If you repay before this period ends, the lender may incur a loss if there is any change in the wholesale rate of interest.