Sending Parcels Abroad With Royal Mail Click & Drop: Customs Forms Explained

Shipping internationally through Royal Mail Click & Drop adds a layer most domestic shippers never have to think about: customs declarations. Get the label right but the customs form wrong, and the parcel can still be held up or returned.

CN22 vs. CN23 — which you need

CN22 is a simplified customs declaration for lower-value parcels (a threshold that varies by destination country), while CN23 is a fuller declaration required for higher-value shipments and typically needs to be attached in a clear plastic wallet on the parcel itself rather than printed as part of the label. Click & Drop determines which form applies based on the declared value and destination you enter, so accurate value declaration matters as much as the address itself.

What customs forms require

Beyond the standard address and weight information used for domestic labels, customs declarations need an accurate description of contents, declared value, and often a commodity/HS code for the item category. Vague descriptions ("goods," "items") are a common cause of customs delays, since they give border officials no basis to process the parcel quickly — a specific description ("printed paper labels," "thermal printer") clears faster.

How this affects your label printing setup

Your printer and label stock setup doesn't change for international shipments — the same 100 × 150mm direct thermal format covered in our 4×6 size guide applies. What changes is the additional customs paperwork that needs printing and attaching alongside it, which for CN23 in particular means planning for an extra physical document rather than assuming the courier label alone is sufficient.

Common causes of customs delays

Beyond vague content descriptions, mismatched declared values (a value that doesn't match the actual item, sometimes deliberately understated to reduce duty) and missing commodity codes are frequent causes of parcels getting held at the border for manual review — adding days or weeks to delivery. Accuracy on the customs form matters more for delivery speed than almost anything on the courier side once a parcel leaves the UK.

Returns on international parcels

International returns are meaningfully more complex than domestic ones, often requiring their own customs paperwork for the return journey — worth planning for upfront rather than as an afterthought if you expect any international return volume, alongside the domestic process covered in our Royal Mail returns guide.