Home / Help / USPS Customs Form Guide
Sign in · Sign up
CN-22 & CN-23, explained

USPS customs forms, handled for you.

CN-22 for packages under $400. CN-23 for everything bigger. Both need 8 fields filled correctly or your package gets held, returned, or hit with surprise duties. Selectido fills both, free, on every shipment.

8
Required fields
$400
CN-22 ceiling
2.7M
Forms USPS files yearly
$0
What we charge
CN-22 vs CN-23

Two forms. One of them applies to you.

USPS uses two different customs declaration forms depending on the value and weight of your package. Picking the right one is the first step — and if you're shipping with Selectido, we pick it for you.

CN-22

The short form

Use when package value is under $400 USD AND weight is under 4 lbs (1.8 kg).
  • Most international shopping packages qualify
  • Single-page green sticker on the box
  • 8 required fields total
  • No dispatch note needed
  • Faster customs clearance at destination
CN-23

The detailed form

Use when value is $400+ OR weight is over 4 lbs.
  • Larger consolidated shipments (multiple US orders)
  • Two-page document inside a plastic envelope
  • 15 fields with itemized line entries
  • Requires dispatch note CP-72 for Priority Mail International
  • More customs scrutiny at destination
Field-by-field

Every CN-22 field, explained.

If you're filling this out yourself, here's what each field actually wants — and the most common mistake at each one. Selectido fills all eight automatically from your order data.

1

Sender name & address

The shipper's full US address. With Selectido, this is our Minneapolis hub.

Common mistake: using a forwarder's PO Box or a fake address. Customs flags it.
2

Recipient name & address

Your full name and address in destination country, including postal code and phone number.

Common mistake: nicknames or partial addresses. Use legal name + complete address.
3

Description of contents

Specific item names — not "merchandise," "gift," or "personal items." Be precise: "skincare cream", "leather wallet", "cotton t-shirt."

Common mistake: vague descriptions. Causes 5-15 day customs delays.
4

Quantity

Number of units per item. "2 jars" not "2 boxes."

5

Net weight (kg)

The actual weight of contents in kilograms, not the box. Convert lbs × 0.4536.

Common mistake: putting gross weight (including box). Customs uses net.
6

Value in USD

Actual purchase price per item. Sale prices count.

Common mistake: undervaluing to reduce duties. This is customs fraud.
7

HS tariff code

The Harmonized System code for the item category. Skincare = 3304, electronics = 8517, etc. Selectido auto-codes from product type.

Common mistake: guessing or leaving blank. Customs assigns the highest rate.
8

Country of origin

Where the item was manufactured, not where you bought it. A US-purchased iPhone says "China" because that's where it's made.

The 5 mistakes that delay packages most

  • "Gift" as description — Customs sees this as evasion. Use specific item names.
  • Undervaluing items — Customs cross-references retail prices. Wrong value = fines + delay.
  • Missing HS code — Customs assigns the highest applicable tariff to unspecified items.
  • Wrong form type — Using CN-22 for a $500 package triggers re-documentation. 5-10 day delay.
  • Unsigned form — Unsigned customs declarations are returned to sender. Full round trip.
Why box size affects customs

Wrong dimensions = paying for empty space twice.

The customs form lists the actual weight of the contents. But international carriers bill by dimensional weight — so an oversized box gets billed twice the rate it should. We repack every parcel to true size before forwarding, so the box matches the form.

Free repack

Small box, small form, small bill.

Example: an 11 lb Sephora order in a 20×16×12 box gets repacked to 12×9×7. FedEx International Economy drops from ~$135 to ~$52. Customs paperwork stays clean because actual weight matches dimensional weight.

As Sephora ships it
20 × 16 × 12 in
11 lbs · DIM 23 lbs billable
$135FedEx Intl Economy
After Selectido repack
12 × 9 × 7 in
9 lbs · DIM 8 lbs billable
$52FedEx Intl Economy
$83
Saved · 61% off
Frequently asked

Questions, answered

What's the difference between CN-22 and CN-23?

CN-22 is a short customs declaration form used for packages worth under $400 USD and weighing under 4 lbs (1.8 kg). CN-23 is a longer form for packages worth $400 or more, OR weighing more than 4 lbs. CN-23 also requires a dispatch note (CP-72) when shipped via Priority Mail International. Most international shopping packages use CN-22; larger consolidated shipments use CN-23.

What information do I need to fill out a customs form?

Both forms require: sender name and address, recipient name and address, description of contents (each item separately), quantity, net weight, value in USD, HS tariff code, and country of origin. The signature certifies accuracy under penalty of customs fraud. Selectido fills all of this from your order data — you never touch a customs form.

What happens if a customs form is filled out wrong?

Three common outcomes: (1) Package held at destination customs for additional documentation — adds 5-15 days. (2) Package returned to sender at your expense. (3) Higher duties charged because the declared value or item description was inaccurate. The most common mistakes are vague descriptions ("gift", "merchandise") and undervaluing the contents. Selectido files accurate, itemized declarations every time.

Can I undervalue items on the customs form to avoid duties?

No — and we won't either. Undervaluing is customs fraud in every country. If caught, the package is seized, you pay penalties, and your shipping history gets flagged. Selectido declares accurate values on every form. Legitimate ways to reduce duties: ship under your country's de minimis threshold (USD $50 for Mexico, $50 for Brazil, etc.), or use gift declarations within country limits.

Why does dimensional weight matter for the customs form?

The customs form lists actual weight, but international carriers bill by whichever is greater between actual weight and dimensional weight. An oversized box can have a dramatically higher billable weight than what's on the customs form. We repack every parcel to true dimensions before forwarding, so the box matches the contents — both for the carrier rate and for clean customs paperwork.

Never touch a customs form again.

Free US suite. We fill CN-22 or CN-23 correctly on every outbound shipment — included in the $14.99 flat fee.

Get my free US address →
Home Help Pricing Forwarding All comparisons