Choosing the right GST accounting basis can be the difference between healthy cash flow and quarterly cash crunches. The payments basis (cash basis) lets you defer GST on unpaid invoices, but is only available below $2m turnover. The invoice basis (accruals) is mandatory above the threshold. This tool tests your eligibility, models the cash flow impact based on your average debtor days, and recommends the best basis for your situation.
You account for GST on sales when you ISSUE the invoice, even if the customer hasn't paid yet. You claim GST on purchases when you RECEIVE the invoice from the supplier, even if you haven't paid them yet. This matches financial accounting and is mandatory for businesses with turnover over $2m. The downside: you can pay GST to IRD on sales before your customer has paid you.
You account for GST on sales only when you actually RECEIVE the cash. You claim GST on purchases only when you actually PAY. Best for cash flow because you never pay GST on unpaid invoices. Available only to businesses with turnover of $2m or less, and non-profit bodies of any size. The vast majority of small businesses use this basis.
Combines invoice basis for sales (you account for GST when you ISSUE invoices) with payments basis for purchases (you claim GST only when you PAY suppliers). Rarely advantageous. Might suit a business with mostly cash sales but very slow creditor payments. Any GST-registered person can elect the hybrid basis.
For a business with $1m annual taxable sales and 45 day average debtor days, the payments basis saves approximately $18,500 of working capital tied up in GST. This is the GST you would otherwise pay to IRD on issued-but-unpaid invoices. Over a long period this is a permanent timing difference favouring the payments basis.
Some businesses below the $2m threshold elect invoice basis voluntarily because:
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