The company registration form generally takes around 15 minutes to complete. Once submitted, the company will usually be registered within 24-48 business hours, depending on the information you have provided is true and correct.
The only exception to this timeframe is where ASIC needs to manually review your company name. If this is the case then you will be advised as you check the availability of the proposed company name. It can take ASIC up to business days to manually review a company registration application.