When reviewing invoices in BigTime, you may notice that the total amount sometimes differs by a penny from the sum of the line items. This minor discrepancy can be confusing, especially when accuracy is essential in financial reporting. Here, we’ll explain why this happens and what it means for your invoices.
Rounding on Time Entries and Expenses
When you enter bill or cost rates in BigTime, such as mileage, these values are rounded for clarity when displayed on the invoice. BigTime processes these entries to display amounts that are easy for your clients to understand, while still accurately reflecting your recorded totals.
Here is an example - given this equation: Hours * Rate = Client Amount. Hours and Client Amount are constants. Only the rate can change.
- Your rate is $133.33 per hour
- You work 0.5 hours
- Your billable cost is 133.33 * 0.5 = 66.665
- BigTime’s front end rounds this up to $66.67
According to the equation below, you can see that we are now off by a penny from our original $133.33.
- Billing Rate = 66.67 / 0.5 = $133.34
Rounding on Invoices
The above rounding example is for the time and expense entries. This also happens at a cumulative scale for invoices. On invoices, there is no rounding at the subgroup, but there is at the line item level. For example, with Subtotal Settings like By Task or By Staff, BigTime will sum each ‘subgroup’ and round its total to 2 decimal places. This will equate to the Line Item Amount(s) seen on the invoice.
Whereas for the total invoice amount, BigTime will sum the original line items and round that Total Amount to 2 decimal places. This can result in a discrepancy between the total invoice amount and the sum of the line items. While this is unusual, the more specific your rates, the more likely these discrepancies become. Sales Tax, if included, is rounded at the overall invoice level, as well.
Minimizing Rounding Discrepancies
If you notice slight differences between the expected line item total and the actual invoice total amount displayed, consider revisiting the time and/or expense entries with longer rates and rectify there.
Large Differences
Differences of more than about 10 cents are generally not due to rounding in calculations. They may indicate a more significant discrepancy or error. You should carefully review your records.
Invoice Total and PDF or Report Total Differ by $0.01
A one-cent difference between an invoice total and a PDF or report total is almost always caused by rounding. It is most common on invoices with many line items, tax calculations, or rates with multiple decimal places. This is expected behavior and not a calculation error. It happens because rounding is applied at different points in the calculation, such as at the line level, at the total level, or when the PDF is rendered.
Symptoms
- The invoice total and the PDF total differ by $0.01.
- The invoice total and a report total differ by $0.01.
- The difference appears on invoices with many line items, tax, or rates with several decimal places.
- Line items appear correct, but the grand total is off by one cent.
Resolution Steps
- Step 1: Export the invoice line detail to a spreadsheet, then add up the unrounded line amounts manually.
- Step 2: Compare your manual total to the PDF total. If they differ by one cent, the difference comes from display rounding on the PDF.
- Step 3: If the line total matches the PDF but differs from the report, the difference comes from how the report applies rounding.
- Step 4: Confirm tax is calculated on the same basis (pre-rounded or post-rounded amounts) on both the invoice and the report.
- Step 5: If your policy allows, add a small adjustment line (+$0.01 or -$0.01) to the invoice so the grand total matches the report, then save the invoice.
- Step 6: If the difference remains, send the following to Support: the invoice number, a PDF export of the invoice, and the report output showing the differing total. Support can confirm the rounding method in use and recommend a configuration change or adjustment.
Best Practices
- Use one rounding approach consistently, either at the line level or at the total level, across invoices and reports.
- Keep tax calculations consistent by applying tax to the same basis on invoices and reports.
- Use a one-cent adjustment line only where your accounting policy allows it. It is an accepted practice for reconciling rounding differences.
- Review invoices with many line items or multi-decimal rates before sending them to clients.