Here's the calculator:
http://www.dutycalculator.com/
Should also say that FedEx don't tend to forget too often, especially when it's a large sum. It is not them that decides on the fees charged on packages but HMRC - that's the bit on the tracking information where it says 'clearing customs'. They then allow FedEx to collect the money on their behalf and that is why FedEx charge a handling fee.
http://www.dutycalculator.com/
Should also say that FedEx don't tend to forget too often, especially when it's a large sum. It is not them that decides on the fees charged on packages but HMRC - that's the bit on the tracking information where it says 'clearing customs'. They then allow FedEx to collect the money on their behalf and that is why FedEx charge a handling fee.