The rounding precision for sales tax calculations is designed for two decimal places in QuickBooks Online, Brad111.
When it comes to sales taxes, Rate/Unit Price fields on invoices have a precision of seven (7) decimal places, whereas the Amount fields for each line have a precision of two (2) decimal places. You can click here to learn more.
Thus, due to rounding issues for many small items with decimals, the GST total may differ when compared to calculating GST directly on the subtotal.
To address rounding discrepancies, manually adjust the line item to ensure it aligns accurately with the sub-total.
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