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High bill checklist

Is your bill higher than usual? Here are some tips to help you learn why

If you’ve received a high electricity bill unexpectedly, it can come as a huge shock. It’s important to understand why your bill might be higher to prevent a shock with your future bills. You might like to:

  1. Check that your bill has not been estimated. If you're not sure, you can find out if your bill has been estimated.
  2. Read through our list of common factors which may lead to high bills below and see if any of these apply to you.
  3. Take action to manage your energy use and the cost of your next bill - or find out what you can do if you might have trouble paying.

To find out why your bill might be higher, consider the following checklist:


Is my energy usage higher than normal? 

In most cases, you might have a higher bill from using more electricity without realising how or why.

Your bill is made up of various items including a daily supply charge, electricity consumption measured in units of power (known as energy usage), other fees and charges, concessions and GST. 

Here’s how to tell if your energy usage has been higher than usual:

  • Take a look half-way down the first page of your bill. You'll see a summary of your energy usage compared to your last bill, and the year before, if that data is available. You can see at a glance if your energy usage is higher than usual.
  • Log in to My Account to find more details about your energy usage. You can also use My Account to help monitor your energy usage in the future.

Why is my energy usage higher than normal?

In most cases, your higher bill might be from using more electricity without realising how or why. Here are some reasons your energy use might have spiked.

A give way street sign and tree foliage in the foreground and shop fronts and glare from the sun in the background

The weather

It is important to consider the weather conditions over your current bill period as well as the bill period you are using to compare your use.

If your bill is showing energy usage to be higher than your last bill, consider which season those bills are covering.  Is this bill for the summer period and last bill for spring when temperatures were lower and your air-conditioning was used less?

If your usage is higher than the same time last year, consider what the weather has been like this year compared to last year. Have we had a cooler winter or warmer summer than last year which may have impacted your usage?

Heating and cooling your home can use large amounts of electricity. Hotter temperatures in summer might mean you have used your air-conditioning more, or run your pool pump more often if you have a pool. If your bill is higher in winter, it might be because you have used your electric heater, electric blankets and clothes dryer more.

Here are some tips for saving energy during hot weather. 

Here are some tips for saving energy during winter.

Woman cooking eggs in frying pan on electric cooktop

Your appliances

We've never relied on energy more. Our modern homes are filled with all sorts of electrical appliances and some of these use a lot more electricity than others. Consider which appliances you have been using and whether you have any new appliances in your home.

Take a look at "Could these 5 ordinary appliances be making your energy use spike?" to learn more and find out what you can do to save energy.

For more information on how to use specific appliances, read your manual, the manufacturer’s website or its ‘energy efficiency’ label. You may find the power rating printed on the back or underneath many appliances. You can also visit for more information.

Try our Energy Tool to find out more about how to reduce your energy usage.


Four house mates hanging out on a sofa in the lounge

House guests and holidays

The more people you have in your house, the more energy you’re likely to use. You might see a spike in your energy costs if a friend or relative stays for a few weeks, or if your kids have been home for the school holidays.

When you go away, it’s also likely that your energy usage would be lower for that period of time. If your energy use for this bill is higher than your previous bill period or the same time last year, think back to whether you were you away at some stage. It is likely that you would have  used less energy while you were away, compared to your current bill.

Person leaning over benchtop, scrolling on mobile phone, with bill and laptop beside them

Billing period

Generally, your electricity meter is read every 2 months. It is rare that your invoice will cover the same exact number of days per billing period. So, if this bill covers a few more days than previous bills, this could explain why your usage might be higher.

Your bill has important account details in the top right corner on the front page, including your account number, invoice date and account period which shows the dates and number days your bill covers. Have a look at the number of days this bill covers compared to your last bill or your bill for the same time last year.

Log in to My Account to look at your previous bills and check how many days those bills covered.

What are the other reasons my bill might be higher?

If you’ve worked through the questions above and found that your energy usage is not higher than usual, take a look at the other components of your bill which might have caused it to be higher.


Do we have your concession details?

If you have a valid concession card, make sure your concession has been applied to your Synergy account. Check to see whether there is a concession amount credited to your bill.

To add or edit your concession card details, you can:

Is there money owing from a previous bill?

If you didn’t pay the full amount of your last bill for some reason, the remainder will carry over to your next bill. This will continue to roll over to each new bill if you don’t pay the full amount each time. Any overdue amounts will be displayed in the account summary information on the front page of your bill.

Your bill account summary displays the details of any payments that we have received since your previous bill was produced.

previous bill image

Payments may take a few days to be cleared to Synergy, so if you made a payment just prior to the issue date of your current bill this may explain it. If you feel that you have not been credited for all your payments since the date the bill was issued please check your payment method, collect your receipts and check your bank statement to ensure the funds have been withdrawn. If you have receipts to confirm a payment has been made but is not shown on your bills please make sure you let us know so we can investigate further.

Was your bill based on estimated meter data?

You might have already confirmed that your current bill is not based on estimated meter data. However, if your previous bill was estimated, then your current bill might include an adjustment if the previous bill estimate was too low or high.

Check the back of your bill for details of any adjustments. This will include details of which bill was adjusted (or ‘reversed’), the date of issue, reversed amount and reason for the reversal.

bill estimated details

Has there been a price increase or change to the energy plan?

Your energy plan or prices can change from time to time. If this is the case, we’ll always let you know. You can check your current bill to see if your prices have recently changed.

On the back of your bill, you'll find a detailed breakdown of your charges and deductions. This includes your chosen energy plan, the price per unit of electricity as well as any concessions or deductions you may be eligible for.