We deliver duty-free to UK. This does mean we don't have to charge 21% Dutch VAT when the delivery address will be in the UK.
This doesn't mean you pay any taxes. You have to pay import duty/tax. You pay this usually to the carrier, they deal with the tax authorities.
You want to buy a product for 1.000,00 € inclusive VAT
The Dutch VAT is 21%: (1.000,00 € / 121) * 21 = 173,55 €
So without 21% Dutch VAT you pay us 826,45 €
You pay import duty/taxes over 826,45 € plus a fee for the carrier. We cannot calculate the exact amount for you, it varies. Take into account 20-25%.