False billing and unsolicited invoices can be actual offers from companies for services like advertising, domain renewals, offering overseas registration or listing in government or other directories.
The business is not doing anything illegal, so long as these offers, samples or ‘free trials’ contain the warning statement required by the ACL – "This is not a bill. You are not required to pay any money". This warning statement must be the most prominent text on the document. There are however many scams that operate in a similar way, like sending false bills to businesses and hoping that the organisation is too busy to check and they just send the money.
Remember, if you have not agreed to buy or receive the goods or service, it is unlawful for a business to request payment.
Consumer Protection have prepared a factsheet to help you better understand this type of unlawful activity and what you can do if you think you have paid a false bill.