Guides

A few featured guides below — browse all 52 guides →

What Is a Customs Broker?

What customs brokers do, when you need one, and how to choose the right broker for your imports.

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How Much Does a Customs Broker Cost?

A breakdown of customs brokerage fees, pricing models, and what to expect when comparing brokers.

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First-Time Importer Guide

Everything you need to know before your first U.S. import — from getting an importer number to filing your first entry.

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USMCA Rules of Origin

How to qualify for preferential tariff treatment under USMCA, including regional value content and tariff shift rules.

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FSVP Compliance

How to meet FDA Foreign Supplier Verification Program requirements and avoid import alerts on food shipments.

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Country of Origin Determination

How CBP determines country of origin, why it matters for duty rates and trade agreements, and how to get it right.

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Hardware Importer Guides

Section 301 for Electronic Components

HTS 8536/8538/8541/8542, China-origin Section 301 stacking, exclusions, PSC/protest candidates, and distributor audit workflow.

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FEOC & EV Battery Imports

Customs-side evidence for battery cells, modules, drivetrain components, UFLPA screening, and IRA Section 30D coordination.

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First-Sale for AI Compute Hardware

Valuation controls for GPUs, accelerators, servers, optics, cooling, and datacenter hardware import programs.

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Importer Workflows

In-Bond Transportation: CBP Form 7512

Understand IT, T&E, and IE in-bond movements before cargo moves under bond between ports, warehouses, and export points.

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Tariff vs. Tax vs. Duty

Use this plain-English explainer when finance, sourcing, and logistics teams use the same cost words differently.

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Shopify & Amazon Customs Compliance

Formal-entry compliance for DTC brands moving from parcel experiments into repeat commercial importing.

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Subscription Box Customs Compliance

Recurring SKU bundles create classification, valuation, and country-of-origin issues. This guide shows how to control them.

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How to Use the Greenwich Resource Library

Start with the guides when you need a decision path: whether a customs bond is required, who pays tariffs, how customs clearance works, which CBP form controls a filing step, or how duty drawback can recover paid duties. Each guide is written for import teams that need to brief finance, operations, and suppliers before a shipment is filed.

Use the customs glossary when a term appears on a broker invoice, arrival notice, CBP request, or ACE report and you need a quick definition. Use the tools when you need to screen a number: HTS candidates, duty exposure, or customs bond size.

If a topic affects a live entry, do not rely on a guide alone. Pair the resource with commercial invoices, packing lists, HTS support, country-of-origin evidence, and broker review before filing.

Glossary

Customs & Trade Glossary

50+ customs and trade terms defined in plain language. From ACE to warehouse entry, every term importers encounter explained clearly.

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