LetterAgent
Mail physical letters by just asking your AI assistant.
Home > Guides > Filling out customs forms
A customs form tells the destination country what is in your parcel, what it is worth, and whether it is a gift, merchandise, or documents. Fill it out completely and honestly: vague descriptions and lowballed values are the two most common reasons parcels get held at the border. Describe each item specifically, declare the real value, and sign it.
This is general information, not tax advice.
For postal shipments, the two common forms are the CN22 (a small green sticker-form for low-value parcels) and the CN23 (a longer form for higher-value or heavier parcels). Your post office or online postage flow chooses based on the declared value and destination. Courier shipments (UPS, FedEx, DHL) use a commercial invoice instead, which carries the same information in more detail: full addresses, item descriptions, values, and the reason for export.
The rule is simple: anything crossing a border needs a declaration attached to the outside of the parcel. No form, no clearance. Customs officers will not open your parcel to figure out what it is; they will hold it, return it, or in some countries destroy it if the paperwork is missing.
As specific as you can make it. Customs officers clear thousands of parcels a day, and "clothes," "parts," or "gift" tells them nothing: those descriptions invite the parcel to be pulled aside for inspection. Write what a stranger would need to identify the item: "men's cotton t-shirts, size L," "stainless steel bicycle crankset," "paperback novels, used."
| Vague (invites inspection) | Specific (clears faster) |
|---|---|
| Clothes | Women's wool sweaters, size M |
| Electronics | USB-C wall chargers, 20W |
| Supplements | Vitamin D3 capsules, 1000 IU, 90 count |
| Parts | Replacement lawn mower blades, 21 inch |
List each distinct item on its own line with its own quantity and value. A box of five different things declared as one line item looks like you are hiding something; five lines looks like a careful shipper.
The real one. Declare what the item is actually worth: the price you paid, or the fair market value for used goods. The declared value does not change your postage; it determines the duties and taxes the recipient may owe, and understating it to dodge those charges is misdeclaration. Customs agencies compare declared values against their own reference data, and a laptop declared at ten dollars will be flagged instantly.
Two honest-value subtleties people miss. First, for a warranty replacement or repair return, declare the value of the goods themselves and note "warranty replacement, no charge" clearly: the item still has value even if the recipient is not paying. Second, for handmade goods, declare what you would sell them for, not what the materials cost. If the recipient gets a duty bill they did not expect, that is a conversation to have before shipping, not after.
Only if it genuinely is one. The gift box on a customs form is not a duty-avoidance trick; it is a factual statement about the transaction, and most countries still collect duties on gifts above a small exemption threshold. Marking commercial merchandise as a gift is misdeclaration, the same as lying about the value.
The exemption itself is smaller than people assume: a few dozen dollars at most in many countries, and it usually applies only to unsolicited gifts between private individuals, not to anything a business sends. If you are shipping inventory to a customer, it is merchandise, full stop, no matter how friendly the relationship.
HS codes are the international numbering system customs uses to classify goods: a six-digit code that identifies what a product is, shared across nearly every country. "Men's cotton t-shirts" maps to a specific code; "stainless steel crankset" maps to another. Postal CN22/CN23 forms for personal shipments usually do not require them, but commercial invoices and courier shipments often do, and some countries now require HS codes even on low-value parcels.
You do not need to memorize them. Every country's customs site publishes a searchable tariff database, and the first six digits are the same worldwide (countries add their own extra digits after that). For a one-off personal shipment, a clear written description is enough; for anything commercial or repeated, look up the code once and reuse it. Getting the code right matters because the duty rate attaches to the code, not to your description.
Ready to ship it? Get a shipping label with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and get your label.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
Need help? Ask your assistant: it can check a job's status any time. If it ever can't handle something: hello@getletteragent.com