CBP Form 434 Historical NAFTA Form Guide

Who uses CBP Form 434?

Exporters, producers, importers, brokers, and auditors reviewing pre-USMCA NAFTA records.
Teams answering a customs request tied to an older transaction or legacy compliance file.
Researchers comparing the former prescribed NAFTA form with today’s non-prescribed USMCA certification.

What to prepare before you start

Build the evidence set first. It is faster and safer than guessing through the PDF and repairing contradictions later.

01
Confirm the shipment date and the trade agreement that actually applies.
02
Collect exporter, producer, and importer legal names and full addresses.
03
Match each good to its commercial description and Harmonized System classification.
04
Retain the origin analysis supporting the preference criterion and country-of-origin entry.
05
Determine whether net-cost calculations were used and the period they covered.
06
Do not copy Form 434 language into a current USMCA certification without checking current rules.

Section-by-section field guide

Form section	What to enter and verify
Exporter and blanket period	Identify the exporter and, only when the certificate covered repeated shipments of identical goods, enter the applicable start and end dates.
Producer and importer	Use the form’s permitted producer treatment and identify the known importer. Preserve the basis for any “available to customs” treatment.
Description and HS classification	Describe each good precisely enough to connect it to the invoice and enter the tariff classification at the required level.
Preference criterion	Enter the NAFTA criterion that the contemporaneous origin analysis supported; this was not a guess based on shipping country.
Producer, net cost, and country of origin	Complete the coded entries according to the form instructions and retain calculations or supplier certifications used.
Certification	The authorized signer certified the accuracy of the information and agreed to maintain and present supporting records.

A reliable completion workflow

1
Verify that the transaction belongs to the NAFTA period or another legitimate historical use.
2
Reconcile parties and goods against invoices, purchase orders, and customs entries.
3
Validate tariff classification before evaluating the preference criterion.
4
Attach the origin evidence and net-cost workpapers to the retained file.
5
Complete the certification only through a person authorized to attest to the records.
6
For a current shipment, stop and use current USMCA certification guidance instead.

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Common mistakes to avoid

Using Form 434 for a post-June 2020 shipment merely because CBP still hosts the PDF.
Treating “made in North America” as proof that an origin rule was satisfied.
Entering an HS code that does not match the import classification.
Selecting a preference criterion without retaining the bill-of-materials or supplier evidence.
Assuming the form’s continued availability reinstates the NAFTA program.

PDF technology note

The hosted PDF is a conventional fillable AcroForm. That makes field extraction straightforward, but the legal applicability question must be resolved before any automation.

Privacy and security

The form contains business contact, supply-chain, classification, and certification data. Keep the completed form and its origin workpapers in an access-controlled trade-compliance file.

Frequently asked questions

Is CBP Form 434 still valid for USMCA?

No. USMCA replaced NAFTA on July 1, 2020, and does not require CBP Form 434. A current certification may use any format that contains the required data elements.

Why does CBP still provide a revised Form 434?

An official hosted copy can support historical records and administrative needs. Its presence does not change which agreement applies to a modern shipment.

What replaced CBP Form 434?

For current qualifying North American trade, use a USMCA certification of origin containing the required minimum data elements. CBP also publishes an optional template.

Can software decide the preference criterion?

Software can organize source records, but the criterion depends on tariff classification, sourcing, and the applicable rule of origin. A qualified trade professional should review that conclusion.

Official sources and research method

We reviewed the official agency landing page, downloaded form structure, visible pages, instructions, and the official materials below. This is an independent preparation guide, not legal, tax, customs, or licensing advice.

CBP Form 434 official page
Official form landing page and current hosted file.
CBP USMCA overview
Current agreement context and implementation resources.

Research and editorial review: Clerks AI Research Team · Last reviewed 2026-07-26

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