Customs on both ends, and who pays for what
Cross-border merchandise crosses customs twice, and the two events are not symmetrical. The export event, in the country of production, establishes what the goods are declared to be for the purposes of statistics, control and any preferential treatment claimed under a free trade arrangement. The import event, in the destination country, is the one that determines duty and tax. Documents prepared for the export side are largely the same documents the import side will ask for, which is why the preparation should be done once, correctly, before production.
The set of documents a cross-border apparel consignment normally needs is short and should be produced from the order, not assembled afterwards: a commercial invoice with a description of the goods and a value, a packing list showing the contents by carton and by item, a transport document, and an origin or movement certificate where a preference is claimed. On top of those, three pieces of information carry most of the risk. The commodity classification code, because the duty rate follows it and because a code chosen for convenience rather than accuracy is the classic cause of a query. The declared value, because an understated value is a legal problem and an overstated one is simply a tax you did not need to pay. And the shipper and consignee details, because a consignment cannot be released to an address that the paperwork does not match.
The delivery term decides who carries which obligation, and buyers should understand the three that matter. Under a term where the seller delivers to the named place cleared for import, the seller pays the freight, the duty and the clearance, and the buyer receives a ready-for-delivery consignment. Under a term where the seller delivers to the carrier at the origin, the buyer pays everything from that point, including the clearance and the duty. The third places the split at the border, which is the model that most often produces a buyer surprised by a bill. Choosing the term is a decision about who is willing to own the customs process, and the right answer is usually the party with the experience of it.
Preferential tariff treatment is worth checking rather than assuming. Where a free trade area or a preference scheme applies, an origin certificate can reduce the duty rate to zero, and the condition is usually that the goods meet a specified origin rule, which for textiles can depend on the fibre content and on how much of the processing happened locally. A preference claimed and then refused is worse than no preference claimed at all, because the refusal converts into a demand for duty plus interest. Confirm eligibility against the actual fabric composition and the actual production steps, and keep the evidence.
Finally, import clearance requires an importer who exists in the destination country and who can be identified on the paperwork. For a company shipping into a jurisdiction where it has no entity, that question has to be answered before the goods are made, not when they arrive at the border. It is one of the most common reasons a perfectly good order is sitting in a terminal.