In general, for a VAT-registered business in the UK:
- sales of goods and supplies of services overseas are zero-rated
- purchases of goods from outside the UK, assume output VAT is paid on import, enter input VAT on VAT return to be reclaimed. There are some exemptions for charities
- purchase of services from outside the UK are usually subject to a reverse charge
The rules are very complex though with numerous variations so do follow up and check. Our guide International aspects of VAT made simple is a useful starting point.