Mixing personal and business money is one of the most common compliance mistakes small business owners make — and one of the easiest to fix. The ATO expects clear separation of business and personal finances, and tangled records make BAS lodgement, tax returns, and audits significantly harder and more expensive.
Open a dedicated business bank account and a separate business credit card. Run all business income and expenses through these accounts only. This creates a clean audit trail and makes bank reconciliation in your accounting software straightforward. Most Australian banks offer fee-free business transaction accounts for small business.
Use accounting software (Xero, MYOB, or QuickBooks are the most common in Australia) connected to your business bank account via a live bank feed. Categorise transactions as they come in — weekly is ideal, monthly at minimum. The longer you leave it, the harder it is to remember what each transaction was for.
For sole traders: even though you and your business are the same legal entity, maintaining separate accounts is still essential. Pay yourself a regular "wage" via transfer from the business account to your personal account, rather than dipping into business funds for personal expenses. This gives you clear visibility of actual business profitability and makes tax time dramatically simpler.