What to Do If You've Received a Catch-Up Energy Bill

A catch-up energy bill (also called a backbill) arrives when your energy retailer discovers you were previously undercharged or not billed for energy you already used. It can land without warning and often covers months of usage at once — leaving many households scrambling to figure out what they owe, what they're actually required to pay, and what protections apply to them. 

This guide explains exactly what to do when you receive a catch-up bill. It covers your rights under Australian energy law, how far back a retailer can charge you, how much time you must be given to pay, and what to do if you think the bill is wrong. 

What Is a Catch-Up Energy Bill? 

A catch-up energy bill covers electricity or gas you used but were not previously billed for. Your retailer sends it once they identify a shortfall between what you were charged and what you actually consumed. 

These bills can cover weeks or even months of usage. Receiving one is disorienting, especially when the amount is significant. The good news is that strict rules govern how retailers can issue them and what you're obligated to pay. 

Semantic relationship: Energy retailers + must explain + the reason for undercharging on the catch-up bill. 

Why Was My Catch-Up Bill Issued? 

Before doing anything else, check the bill carefully. Retailers are required to clearly state why the undercharge occurred and which period the bill covers. 

Common causes include: 

• Bills were based on estimated meter readings that turned out to be lower than actual usage 
• A meter reading error recorded less usage than you consumed 
• A billing system problem caused the retailer to miss issuing a bill on time 
• An incorrect meter reading from a previous billing cycle 
• A faulty smart meter or data transmission problem that delayed usage information reaching your retailer 

If the explanation on your bill is unclear, call your retailer and ask them to specify the cause. You can also request your billing history — retailers must provide up to two years of historical billing data upon request, according to Energy and Water Ombudsman NSW (EWON). 

How Far Back Can a Retailer Charge You? 

This is where your consumer protections matter most. The rules differ depending on your state or territory and whether the billing error was your fault. 

If the Undercharging Was NOT Your Fault 

• In NSW, Queensland, South Australia, Tasmania, and the ACT: 

The National Energy Retail Rules (Rule 30) set a nine-month limit. Retailers cannot bill you for usage further back than nine months from when they notified you of the undercharge, if the error was theirs. 

• In Victoria: 

The ESC tightened protections from 1 January 2021. Retailers can only recover amounts undercharged in the four months before they notify you — not nine — if you were not at fault. This applies under Victoria's Energy Retail Code of Practice. 

Semantic relationship: Victorian ESC + reduced backbilling limit + from nine months to four months (effective 1 January 2021). 

If the Undercharging WAS Your Fault 

The backbilling restrictions generally do not apply when you caused the undercharge. Examples include: 

• You prevented meter access (e.g., a locked gate or a pet blocking the meter reader) 
• You tampered with the meter or interfered with readings 
• The undercharge resulted from your own unlawful act or omission 

In these situations, the retailer may be entitled to recover a larger amount, potentially going back further than the standard limits. 

Important: Rules vary by state and territory. Always check with your state's energy regulator or ombudsman for the most current guidance applicable to your situation. 

How Long Do You Have to Pay? 

You do not have to pay the entire catch-up bill in one go. Australian energy rules require retailers to offer you time to pay. 

The Standard Rule 

According to EWON (Energy & Water Ombudsman NSW) and EWOV (Energy and Water Ombudsman Victoria), the retailer must give you at least the same amount of time to pay as the period covered by the backbill — up to a maximum of 12 months. 

• Example: If the catch-up bill covers six months of undercharged usage, your retailer must give you at least six months to repay it. 
• Example: If the undercharged period was 14 months, the maximum repayment period is still capped at 12 months. 

What You Can Request 

When you contact your retailer, ask about: 

• Instalment plans — spreading the catch-up amount over multiple payments 
• Bill smoothing — averaging your payments across the year to reduce spikes 
• Extended payment arrangements — especially if you are experiencing financial hardship 
• Flexible due dates — aligning payment dates with your pay cycle 

Semantic relationship: Energy retailers + must offer + equal time to pay a catch-up bill, capped at 12 months. 

Do I have to pay a catch-up bill all at once? 

No. Retailers must offer you extra time to pay. Under the National Energy Retail Rules and Victorian Energy Retail Code, you must be given at least the same amount of time to repay the backbill as the period you were undercharged — up to a maximum of 12 months. 

What If You Can't Afford the Bill? 

If you're struggling to pay, the most important step is to contact your retailer as soon as possible. Do not ignore the bill. 

Hardship Programs 

Under Australian energy law, retailers must have a customer hardship policy in place. Energy Made Easy (the Australian Government's energy comparison service) confirms that, by law, energy retailers must offer to set up payment plans for residential customers who are having trouble paying their bills. 

Support available through hardship programs may include: 

• Flexible payment arrangements tailored to your income 
• Payment deferrals or extensions 
• Access to energy concessions or government rebates 
• Advice on reducing your energy usage to lower future bills 
• Referrals to financial counselling services 

Semantic relationship: Energy hardship programs + are required by law + under the National Energy Retail Rules. 

Government Concessions and Rebates 

Depending on your state and personal circumstances, you may be eligible for concessions or rebates that can reduce what you owe. Contact your state government's energy department or check the Energy Made Easy website for current scheme information in your area. 

What If the Bill Seems Wrong? 

A catch-up bill is not always correct. Billing errors happen — and you have every right to question one. 

Step 1: Contact Your Retailer 

Raise your concerns in writing if possible. Ask the retailer to: 

• Explain the cause of the undercharge in detail 
• Provide the billing records and meter data for the period in question 
• Confirm that the back-billing period does not exceed the legal limit for your state 

Keep records of every conversation, including the date, the name of the person you spoke to, and what was agreed. 

Step 2: Escalate to the Energy Ombudsman 

If your retailer does not resolve the dispute to your satisfaction, you can escalate — free of charge — to your state or territory energy ombudsman: 

Ombudsman services can investigate billing disputes, review whether the retailer followed the correct process, and make binding decisions where appropriate. 

Semantic relationship: Energy ombudsman services + provide free dispute resolution + for billing complaints. 

Comparison: State-by-State Backbilling Rules at a Glance 

Note: These rules reflect current Essential Services Commission & Australian Energy Regulator official guidance as of publication. Rules can change. Confirm current protections with your state energy regulator or ombudsman. 

Common Mistakes to Avoid 

• Ignoring the bill. Not responding will not make the bill go away. Unpaid amounts can lead to disconnection. Contact your retailer promptly. 
• Paying the full amount immediately if you can't afford it. You are entitled to a payment plan. Ask before you pay. 
• Assuming the bill is correct. Check the dates, the cause, and whether the period claimed falls within the legal limit for your state. 
• Not keeping records. Always document your communication with the retailer. Written records protect you if the dispute escalates. 
• Waiting too long to escalate. If your retailer is unresponsive or dismissive, go to your ombudsman without delay. There are no fees. 

FAQ 

What is the difference between a backbill and a catch-up bill? 

They are the same thing. "Backbill" and "catch-up bill" are used interchangeably. Both refer to a bill your retailer issues to recover charges for energy you used in a previous period that was not included in earlier bills. 

Can my energy retailer charge me interest on a catch-up bill? 

No. Retailers cannot charge you interest on the undercharged amount being recovered through a backbill. This is confirmed by EWON's backbilling guidance under the National Energy Retail Rules. 

What if my catch-up bill is for more than nine months of usage? 

If the billing error was the retailer's fault and you are in a NERR jurisdiction (NSW, QLD, SA, TAS, or ACT), they cannot recover more than nine months of undercharged amounts. In Victoria, this limit is four months. Any usage outside the allowable period cannot legally be charged to you. 

How do I know if I'm being back-billed correctly? 

Check the bill for:

1. a clear explanation of why the undercharge occurred,
2. the specific period the bill covers, and
3. confirmation that the period does not exceed the limit for your state.

Request billing records and meter data from your retailer if anything is unclear. 

What happens if I refuse to pay a catch-up bill? 

Refusing to pay without a valid dispute can put your account in arrears. This may affect your energy supply. If you believe the bill is incorrect, raise a formal dispute with your retailer in writing rather than simply not paying. Contact your ombudsman if the retailer does not respond fairly. 

Can I switch energy providers while a catch-up bill is outstanding? 

Generally, an outstanding debt with your current retailer can affect your ability to transfer to a new provider. Resolve the dispute or arrange a payment plan first. You can compare energy plans to see your options, but confirm your account status before switching. 

Are small business customers protected by the same backbilling rules? 

Small business customers who use less than 40 MWh of electricity or 1,000 GJ of gas per year are typically covered by the same protections under the Energy Retail Code of Practice (Victoria) and the National Energy Retail Rules (other states). Larger commercial customers may not have the same protections — check with your retailer or regulator. 

Ready to Review Your Energy Plan? 

A catch-up bill is a good reminder to check whether you're on the ideal energy plan to begin with. If your bills have been higher than expected or you're not sure what you're currently paying, comparing plans could help. 

Compare energy plans with electricityprovider.com.au and see what's available in your area today. 

Disclaimer: The content provided is for informational purposes only and is based on publicly available information. While efforts are made to ensure accuracy, readers should independently verify all details with relevant energy retailers or providers. Electricityprovider.com.au may earn a commission from selected providers when users switch energy plans via its platform. Not all plans or providers available in the market may be included in the comparison, and availability can vary depending on location and eligibility. This content does not constitute professional advice.