Trade31Global Trade Toolkit
Trade ToolsKnowledgeResourcesOnline ToolsSearch⌘K
Home/Trade Knowledge/Customs/How Import Duty Is Calculated

Customs

How Import Duty Is Calculated

Tutorial: customs value × duty rate, HS classification, origin proof, and worked arithmetic.

Reading time: 9 min read·Updated: 2026-06-30·Author: Trade31

Duty = Customs value × Applicable rate. Confirm HS code, origin, and any additional tariffs.

Table of Contents

  1. Basic Formula
  2. HS Classification
  3. Origin and Preferential Rates
  4. Additional Duties
  5. Payment and Declaration

Basic Formula

Import duty = Customs value × Duty rate

Customs value is set per national law — commonly CIF at port of entry. Rate comes from tariff schedule keyed to HS code digits.

HS Classification

Correct HS code determines rate and any import licenses. Binding rulings reduce dispute risk for new products.

6-digit HS is harmonized; countries add national suffix digits.

Origin and Preferential Rates

Same HS code may have MFN vs FTA rate. Importer must present valid COO format accepted by customs.

Non-preferential COO still proves origin for rules other than duty.

Additional Duties

Anti-dumping (AD), countervailing (CVD), safeguard, or Section-style trade remedies add on top of base duty.

Check trade remedy databases when sourcing from sensitive origins.

Payment and Declaration

Broker files entry; duty paid before or at release depending on regime. Penalties for misdeclaration include fines and increased inspection rates.

Examples

Numeric

CIF USD 20,000 · Rate 7% → Duty USD 1,400 before VAT.

Preferential

Same CIF · MFN 7% vs FTA 0% with COO → USD 1,400 saved on duty alone.

FAQ

Duty on freight?
If customs value is CIF, freight is inside the base — duty applies to freight portion too.
Minimum duty?
Some lines have specific or minimum duties per unit — check tariff notes.
Currency of duty?
Declared in local currency per customs FX table on entry date.
Provisional duty?
Under review cases may use deposit pending final rate.
Relief programs?
Zones, temporary admission, and aid imports may reduce or defer duty.

Related Tools

  • TrendingUp

    Landed Cost Calculator

    Estimate total import landed cost: CIF + duty + VAT + destination charges. Runs locally.

  • Ship

    CIF Calculator

    Calculate CIF price from FOB, freight, and insurance rate. Local browser processing.

Related Articles

  • Import Duty and Landed Cost

    How import duty fits into landed cost — customs value, HS codes, preferential rates, and compliance.

  • What is Landed Cost?

    Landed cost is the total expense to get imported goods to your warehouse — product, freight, duty, taxes, and handling.

  • What is a Certificate of Origin?

    Certificate of Origin (COO) proves goods origin for preferential duty and compliance — types and issuance.

Related Resources

  • Commercial Invoice Excel Template (Professional)

    Enterprise-ready commercial invoice workbook with Invoice, Packing List, and Instruction sheets. Includes Seller/Buyer, Incoterms® 2020, HS codes, bank details, and filled examples aligned with international trade practice.

Conclusion

Validate HS and rate before PO placement. Link duty results into Import Duty and Landed Cost.

Trade31 — Global Trade Toolkit · practical tools and knowledge for international trade.

Trade ToolsKnowledgeResourcesOnline Tools
AboutPrivacy PolicyContact

© 2026 Trade31