Importing research peptides: customs paperwork, brokers and landed cost

Describe the goods honestly, every time

The commercial invoice and the customs declaration must describe what is actually in the box, with a real value. Some suppliers offer to label research peptides as something else, or to write a low value to cut the duty. Say no. Misdescribed or undervalued goods can be seized, and the penalties land on the importer, which is you.

• Ask the supplier for a commercial invoice that names each product, the quantity, the amount per vial and the true price paid.
• Make sure the invoice, the packing list and the lot numbers on the vials agree with each other.
• Keep a copy of every invoice, packing list and tracking record with the batch it created.

Hire a customs broker

A licensed customs broker files entries for you, classifies the goods, tells you the duty rate and deals with customs when a shipment is questioned. For anything beyond an occasional small parcel, a broker saves more than they cost.

1. Find a broker who already handles chemical or laboratory goods. Ask them directly whether they will work with research peptides.
2. Give them the supplier's invoice and product list before the first shipment, not after it is held.
3. Ask them to classify each product and give you the current duty and tariff rate in writing. Do not guess the classification yourself.
4. Ask whether you need a customs bond, and which option suits the size and frequency of your shipments.
5. Agree how you will be told about holds and what they need from you when it happens.

Duties, tariffs and the end of duty-free small parcels

Duty depends on how the goods are classified and where they come from. Goods from China have carried extra tariffs for several years, and the rates have changed repeatedly, so a figure you read last month may already be out of date. Your broker gives you the current number for your products.

The duty-free exemption for low-value parcels, which many small sellers relied on, was suspended in 2025. Plan on paying duty and brokerage on every shipment, including small ones, and build it into your price.

Holds, inspections and delays

Shipments can be held for inspection by customs or referred to other agencies, and held goods can be released, refused or destroyed. You cannot control that decision, but you can control how ready you are for it.

• Order early enough that a two or three week hold does not leave you out of stock.
• Split large orders across shipments so one hold does not stop everything.
• Keep the documents your broker may be asked for in one folder per shipment: invoice, packing list, supplier details and the lab reports for each lot.
• Agree with the supplier in writing who pays if a shipment is refused or lost.

If a shipment is held, let your broker handle the conversation. Do not contact customs yourself with a different story from the paperwork.

Work out the landed cost per vial

The price on the supplier's sheet is only part of what a vial costs you. Landed cost is everything you paid to get it onto your shelf, divided by the vials you can actually sell.

Add them up, divide by the vials that passed, and then by the milligrams per vial. Our guide to cost per milligram has a worked example with shipping and duties, and the cost per milligram calculator does the arithmetic.

Doing it in Purity

In Purity you draft a purchase order per supplier, record freight, duty and other costs against it, and receive it against what actually arrived. Landed costs are spread across the vials, so each batch carries its true cost, and received stock waits in quarantine until its lab report passes. You can set an arrival date so late shipments show up before they become a stock problem. See it on the demo.