Customs forms are not required if you are shipping domestically (within the same country) or within the EU. These shipments do not go through customs clearance.
All other international shipments require customs forms.
You can complete customs forms using the customs system in your My Orders. Some countries may require additional documentation. If specific forms are needed for your destination country, you will see this information on your customs page.
Important: Since the UK left the EU, customs forms are now required for all shipments between the EU and the UK. This does not apply to domestic shipments or shipments between Northern Ireland and the EU.