Butel software BV resides in The Netherlands. we charge tax under EU/Moss regulations.
Your address details are required to determine if you must pay sales tax. We do not share/sell/lease your address details.
EU: All EU customers must pay sales tax. Because we deliver intangible goods the tax depends on your country (EU/MOSS regulations). EU tax is shown at checkout. Tax paid is shown on your PDF invoice.
UK: UK residents do not pay sales tax.