Some destinations will not release a parcel until customs has an identification number for the person receiving it. Taiwan, Brazil, Chile, China, Mexico and India require the recipient's tax ID or national identification number. South Korea requires a PCCC (Personal Customs Clearance Code) instead. Turkey has the same requirement, but cannot currently be selected at checkout — see Countries we cannot ship to.
This is set by the destination country, not by us. Without the number, customs may hold the parcel, ask the recipient for further documents, or send the shipment back to us.
If your order needs one, we will email you before it ships and ask for it. Replying to that email is all you need to do. You can also send it to us first — message us here, or email [email protected], with your order number and the tax ID or PCCC. If the parcel has not been dispatched we will put it on the customs paperwork; if it has already gone we will pass it to the carrier, though that takes longer to clear than having it up front.
Two things worth knowing. The name on the order must match the name on the ID — that is the most common reason a parcel is held or returned, so if the ID belongs to a partner, a parent or a company, tell us before dispatch and we can usually change the recipient name. And please do not send an identification number through a public chat, a social media message or a forum. Email is the safe route.
There is more detail in "Customs information we may need from you".