Add the yearly costs
Enter annual wage or owner drawings, an annual superannuation allowance, and vehicle, insurance, tools, phone, software and other business costs. Use costs excluding recoverable GST where applicable; avoid counting an expense twice.
Count the hours you can bill
Multiply billable hours per week by working weeks per year. Allow for holidays, quoting, admin and travel you cannot bill. Total yearly cost divided by these hours is the break-even cost per billable hour.
Add your target profit
Add your desired profit per hour to break-even for the ex-GST rate, then multiply by 1.10 for the GST-inclusive estimate. Materials and job-specific charges need separate allowances. This does not calculate income tax or super obligations.