The latest version of WHMCS introduced a new method to calculate tax on invoices. From 7.4 onwards tax is calculated and rounded per invoice line instead of the total tax amount. This has sparked a discussion on where and when you should round tax on an invoice. In the EU both methods are allowed but you can't use them together.
We import all invoices into separate accounting software. We have done this for the last 8 years or so and it has never been a problem until WHMCS 7.4. Our accounting software rounds tax at the invoice level instead of rounding it per invoice line. As a result we are left with 1 or 2 cent gaps. This gap can grow depending on the number of lines on an invoice. This means a lot of extra work is needed to correct these gaps as our accounting software doesn't have an option to switch to a different calculation method. It also means we have to explain to customers how are calculation is somewhat different to theirs as apparently we're not the only ones using accounting software that rounds it on the invoice level.
Instead I would like to have an option to decide where and when tax will be rounded. Either per invoice or per invoice line item.