Wild stab in the dark, but does anyone know if it's possible to change floating point accuracy for shipping items without affecting other areas? We're UK based and having issues with tax rounding, ie. we charge £1.95 shipping. It's not possible to set this excluding tax to two decimal places with a 20% tax rate. £1.62 + 20% = £1.94. £1.63 + 20% = £1.96. We need to be able to set the price before tax to 1.624

You could do the calculation yourself to 3 decimals and store it somewhere non-native but if its native functionality, currencies get 0 or 2 decimal place precision. There's no concept of 3 decimals for US/UK currencies so it wouldn't make sense to do so. Check out SuiteAnswer: 7727

Thanks @creece. The shipping service is being added by a client script, so I may have to try setting the sales price including tax.