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I don't recognise a number charged on my bill

This article provides possible answers to unrecognised numbers showing as dialled / messaged on your phone bill or in My Account.

Select an option for more information.

What's a Local Call?

These are calls that originate from within the same; or from an adjacent standard charging zone / area. Local call access may also be designated to calls travelling to non-adjacent zones, where those zones may have a mutual local interest. Local calls are usually untimed.

A list of adjacent charging zones can be found in the Fixed Line Phone Standard Form of Agreement (SFOA).

What's a Community Call?

These are calls that would otherwise be charged at full national (STD) call rates as the standard charging zone / area in which the call originates is not next to the standard charging zone in which the call is received. 

However, we (Optus) have designated that these 2 areas have a mutual community interest and therefore we charge a reduced national (STD) call rate between the 2 zones / areas. To separate them we've named these reduced rate national (STD) calls, "Community Calls".

Further information about Community Calls is available in the Fixed Line Phone Standard Form of Agreement (SFOA)

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What are 13 / 1300 numbers?

These calls are usually to companies and services. e.g. insurance, banks, government and community services, telephone or internet providers, utility companies etc.

The 13 / 1300 prefix when called from your phone enables the call to travel a national or international distance for only a flagfall cost (these calls are usually un-timed).

What else uses 13 / 1300 numbers?

Examples of other services that may use 13 / 1300 numbers are:

1. Voicemail services

When you dial *96 to retrieve your messages from your Optus Telephony service this can appear on your bill as a call to 1300 721 896. Please see www.optus.com.au/standardagreements for the costs involved with voicemail

2. Home / Office security alert and monitoring systems

Many of these systems can call 'back-to-base' automatically via a 13 / 1300 or Local call number to confirm their status or to electronically report on events, failures or to alert the company of an incident

3. Medical alert and / or 'in home' health monitoring systems

Does anyone in your premises have a wearable medical alert or uses a hard-wired medical alert system? These systems can use local call or 13 / 1300 numbers to automatically report on status, events or failures

4. International card services

13 / 1300 numbers are often used to access international calling card services

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What are 19 / 1900 Numbers?

19 / 1900 numbers were typically assigned to information, competition or voting lines for example, reality / talent TV or radio shows and are sometimes called Premium services.

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What are 0019 numbers?

'0019' is an alternative to the standard international exit code '0011'. The difference is that calls via 0019 force (or 'preselect') the call to travel via the Optus Long Distance network, regardless of who normally bills you for your phone service. 0019's primary purpose is to carry international fax/data traffic hence the name 'Faxline', however, 0019 can also be used for regular voice calls.

What can cause 0019 numbers?

These calls may be manually dialled by an individual, used by a fax or data line or connected via a Dial-Up modem. If a Dial-Up modem is using a 0019 number, then your modem may have been hi-jacked (known as 'modem jacking').

Modem jacking

Modem jacking is often a symptom that malicious software is on your computer. If your modem has been 'jacked', we recommend that you contact us to bar international access via the Optus Network. We also suggest that you contact your internet service provider for assistance with the removal of any malicious software from your computer.

Call us on 133 937

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What are 019 Local Calls?

019 Local call numbers are commonly provided by Internet Service Providers (ISPs) to Dial-Up Internet users, to ensure they're not charged more than a local call when logging in to the internet.

What could be the cause?


1. Using a Dial-up modem

Compare the calls with your login times. If you find there’s a major discrepancy your dial up modem may be timing out and automatically re-dialling to maintain an open internet connection or 'session'.


Note. You may be able to talk to your ISP about changing your computer's settings (i.e. increasing session time-out lengths etc.), to minimise the number of dial-up calls your modem is making.

2. Do not have a Dial-up modem

Check there is not a phone line is still connected to an internal or external dial up modem

3. Medical alert and / or ‘In home’ health Monitoring system

A wearable medical alert or a hard-wired medical alert system may use local call numbers to automatically report on status, events or failures

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Before disputing a charge on your bill, check the time and date of the unrecognised call / message and ask yourself or others at the premises:

  • Has anyone else had access to your premises and could have used your service (e.g. family member, friend, trades-person, business associate, neighbour, etc)?

  • Do you have a 'back to base' alarm?

  • Do you have a medical alert / alarm system?

  • Did you have call forwarding or a call diversion active?

  • Do you have a fax machine, EftPOS or other pay terminal / POS connected to the phone line?

  • Is there a dial up modem (still) connected to a phone line?

  • Do you have Pay TV?

  • Do you have any other appliances connected to your phone line (e.g. 'Smart' appliances that could be reporting back the manufacturer, etc.)?

  • Was anyone staying or visiting you on the day(s) of the call?

  • Did anyone message / call a 19 / 190X number to enter a competition, vote or call an information line?

  • Has the number / call appeared on your bills before?

  • Does the time / date of the call show a consistent pattern / interval between calls?

  • Has anyone used a phone card or international calling card?

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