Understanding Gas Bill: What It Covers and How It’s Calculated

When your bill arrives, it’s common to have questions. You might wonder what the gas bill covers beyond the total amount or be curious about the different charges and meter readings.

Before contacting your gas installation service, you can learn from this article. We’ll explain each part of your bill and why some charges might change. Keep reading to learn more.

What is On Your Gas Bill?

Your gas bill is an official statement from your gas company. It includes your personal information, the company’s details, and key billing information.

The core information shows your total gas usage, the amount you need to pay, and the due date. It often also breaks down the charges for gas consumed, daily supply fees, and any adjustments like credits or fees.

However, different companies may have varying layouts or preferences for what details to display to their customers. Some use a single page for conciseness, while others use up to three pages for readability.

Here is what you’ll see in the main page:

• Customer Name and Account Number — Your customer name and account number are usually at the top of your gas bill. They include your full name and a unique number from your gas provider.
• Supply Address — This shows the exact street address where the gas is delivered, including the postcode. It makes sure the bill is for your property and helps if you have multiple homes.
• Invoice Number and Bill Date — The invoice number, like INV-987654, is a unique code for this bill. The gas bill date, such as 11 September 2025, shows when it was issued. Together, they help you track payments.
• Billing Period — It shows the start and end dates of your usage period. For monthly bills, you might see something like 10 August to 10 September 2025. For quarterly bills, it might be 1 June to 31 August 2025.
• Due Date — This is the deadline to pay the bill and avoid late fees. It is usually 14 to 28 days after the bill date and may include a note about penalties.
• Meter Details — often referred to as MIRN, which stands for Meter Installation Registration Number. This is a unique 10- to 11-digit code for your gas meter, along with the meter’s serial number.
• Meter Readings — They tell you how much gas you’ve used in megajoules (MJ). They show the starting and ending numbers, marked as actual (“A”) or estimated (“E”).
• Gas Usage — This shows your total gas consumption in megajoules (MJ). It is calculated from your meter readings, adjusted for factors like heating value and pressure.

On the back of your gas bill or on the second page, you will often find a breakdown of the calculation. This is usually presented in a table or a simple list:

• Conversion Details — Some gas companies provide this information. It shows how raw meter readings in cubic metres convert to megajoules (MJ). It uses factors like heating value, pressure, and temperature.
• Usage Charges — These variable costs are based on your gas usage, measured in cents per megajoule. There are different rates for initial and additional consumption. It charges only for what you use.
• Daily Supply Charge — This is a fixed daily fee to maintain your gas connection, regardless of usage. It covers the infrastructure costs like pipes and meters, ensuring a reliable supply.
• Total Charges Before Tax — This amount covers all usage and daily supply charges before adding GST.
• GST (10%) — A 10% Goods and Services Tax is added to your total charges as required by Australian law. It is typically shown separately or included in the final amount to ensure compliance.
• Discounts or credits — These reduce your bill for things like on-time payments, bundling with electricity, or loyalty rewards, and are shown as a deduction. They’re intended to incentivise good habits and retain customers.
• Adjustments — If any, this refers to corrections from previous bills. These may include refunds for overcharges or additional fees for underpayments, often with explanations.
• Account Balance — This reflects any previous amounts, such as a credit (overpayment) or a debit (amount owed from before), that affect your total amount payable.
• Total Amount Due: This is the total amount you need to pay by the specified due date. It is usually listed on the first page of your gas bill for easy reference.

Sometimes, your gas company might add extra details, like a quick usage summary or tips to pay your bill more easily:

• Payment Methods — This section shows options like BPAY, credit card, direct debit, or in-person at the Post Office, sometimes with codes or barcodes. Any discounts or incentives for specific methods are also noted.
• Usage summary — Usually shown as a graph, it provides a visual chart of your average daily or monthly gas use in MJ. It often compares your current usage to previous periods. This helps you see usage patterns.
• Tariff Name — If your gas company offers multiple plans, this states your current plan name, such as Standards or Basic. It also includes details like the rate structure and the contract end date.
• Personal Projection — This is extra information which estimates your yearly gas costs based on current usage, usually shown annually or monthly. It helps with budgeting and tracking if you’re overspending.
• Cheaper Tariff Suggestions — This section offers promotions that can help you find better prices or plans, leading to potential savings. It also provides instructions on how to switch.
• Emergency Contact — This provides 24/7 phone numbers to report leaking gas meter  issues. Having this information is important for safety.
• Supplier Contact Details — This is your retailer’s phone number, email, website, and working hours. It helps you easily ask questions or report problems.
  

What Affects Your Gas Bill?

Now you understand what a gas bill covers. However, if you notice that your bill varies each month, you need to understand what might be causing those fluctuations:

• Seasonal weather changes — Your gas use changes with the seasons. Cold weather means more heating, hot water, and cooking, while warmer months use less. This variation affects your bills.
• Billing periods — Gas bills don’t always come monthly. They can be bi-monthly, quarterly, or based on meter readings. The length of the billing period affects how the fixed daily supply charges accumulate.
• Gas consumption patterns — If you work from home, you might cook, heat your house, and use hot water more often. This can make your energy use go up by 10–20%, depending on how many people live with you.
• Different equipment used — Using different appliances can impact your gas bill. Inefficient models consume more gas, leading to higher costs, while selecting Energy Star-rated appliances can reduce it over time.
• Number of people using gas — The more people you have at home, the more gas you will use for cooking, baths, and heating. If you have visitors, that can also increase your usage and your bill.
• Holidays — Having more holidays means more time away from home, which can help lower your gas consumption. However, fixed daily supply charges will still apply.
• Discounts and Promotions — Your gas company may offer temporary discounts, such as up to 10% off for on-time payments or bundled and seasonal deals. These are shown in the adjustments section of your bill.
• Meter Reading — If your meter is hard to access, your gas company may estimate usage based on past data. An “E” on your bill indicates an estimated read, while an “A” shows an actual one. If you notice any problems with your meter reading, consider checking for gas meter adjustment.

FAQ About Gas Bill

These are some common questions people ask about their gas bills:

1. What is the gas bill?

Your gas bill is a detailed statement of your natural gas charges, including fixed daily network fees and variable costs based on consumption. It also shows 10% GST, discounts, and adjustments.

Sent monthly or quarterly, it usually includes meter readings, usage graphs, and payment info to help you understand your costs.

2. Is gas cheaper than electricity in Australia?

Gas is usually cheaper per unit than electricity, though this depends on appliances, location, and plans. It takes about 3.6 MJ of gas to equal 1 kWh of electricity, but gas charges are typically lower.

For example, the average gas bill for a Melbourne household can range from around $100 to $250. But if you use electricity for the same needs, the average monthly bill can be roughly $110 to $160 a month.

3. What does gas cover in a household?

Gas powers many of our key appliances like stoves, water heaters, space heaters, dryers, and fireplaces. It heats and cooks quickly and reliably. But not every home uses it for everything.

Conclusion

By now, you understand what your gas bill covers: meter readings, daily supply charges, and adjustments. These are the main parts of your bill.

You also know that your bill can change from month to month. Weather, billing periods, or hosting guests can all affect the amount.

But remember that every bill is a bit different. If you’re unsure or need help, you can reach out to us at Melbourne Gas Plumber. We’re here to support you with clear advice and solutions.