Nohena Insights · Policy & Tariffs
How the CET review affects your import duties
A CET review directly affects your import duties by changing the base tariff rates, creating new tariff classifications, and altering supplementary levies that impact the final customs value calculation.
Nohena · 21 October 2026 · 8 min read
How the CET review affects your import duties
A CET review directly affects your import duties by changing the base tariff rates for specific goods, splitting or creating new tariff classifications, and altering the national list of supplementary levies and prohibitions.
The ECOWAS Common External Tariff, or CET, is the foundational document for calculating customs duty on most goods imported into Nigeria from outside the economic bloc. Its periodic review is a significant event for every licensed agent and importer. Understanding the mechanics of a CET review is not an academic exercise; it is a core competency for accurate cost forecasting and compliance. These reviews are not simply about rates going up or down. They can reshape the very structure of the tariff book, creating compliance risks for those who rely on outdated classification data.
This analysis details the practical consequences of a CET review on your duty calculations and outlines a preparatory framework. For more analysis on Nigerian trade policy, you can visit our insights page .
What is the ECOWAS CET review?
The CET review is a periodic, multilateral process where ECOWAS member states update the common tariff applied to goods imported from outside the region. The goal is to create a unified customs territory, foster regional industrialisation, and harmonise economic policy. Nigeria, as a member state, implements the CET through the Nigeria Customs Service (NCS), publishing it as the national tariff book.
The CET is built on the Harmonized System (HS) nomenclature and is structured into five primary tariff bands:
0% for essential social goods like medical supplies and educational materials.
5% for raw materials and capital goods.
10% for intermediate goods.
20% for finished goods.
35% for specific finished goods given extra protection for local manufacturing.
A review process, typically occurring every few years, adjusts this structure based on economic priorities, technological changes, and trade negotiation outcomes. The result is a new version of the tariff that all importers and their agents must adopt from its effective date.
How a CET review changes your duty calculation
A CET review changes your duties by directly modifying the tariff rate applied to your product's HS code or by altering the code itself, which can cascade into higher or lower final payable amounts. These changes are not always straightforward and can manifest in several ways, each requiring careful attention during declaration preparation.
Direct tariff rate adjustments
This is the most obvious impact. A CET review can move a product from one duty band to another. For example, a specific type of industrial machinery previously at 5% might be moved to 10% to encourage local assembly, or a finished consumer good might be moved from 20% to 35% to protect a nascent local industry. These adjustments directly increase or decrease the base duty component of your total customs cost.
HS code restructuring and reclassification
Perhaps the most subtle and risk-prone aspect of a CET review is the change to the HS codes themselves. A review often aligns the tariff with new versions of the World Customs Organization's Harmonized System. This can lead to:
Splitting codes: A single 10-digit HS heading for a product like 'solar panels' might be split into two or more new headings, for example, 'fully assembled solar panels' and 'solar panel components', each with a different duty rate.
Merging codes: Conversely, several distinct codes for similar items might be consolidated under a single, broader heading.
Creating new codes: New technologies or products that did not exist during the last review may be assigned their own unique HS codes.
Continuing to use an old HS code after a review is a common source of compliance flags, potentially leading to interventions, delays, and demands for uplift on the Pre-Arrival Assessment Report (PAAR).
Changes to national lists and supplementary levies
The CET is a common *external* tariff, but each country retains the right to apply additional national charges or maintain lists of exceptions. A CET review is often accompanied by updates to these national lists in Nigeria, including:
The Import Prohibition List (Trade): Found in Schedule 3 of the CET, this list details items that cannot be legally imported. Items can be added or removed during a review.
The Supplementary Excise List: Schedule 5 lists goods subject to specific excise duties on top of the standard import duty, such as was implemented for certain beverages and telecommunication services.
Import Tariff Reduction (ITR): The government may grant time-bound concessions on certain raw materials and capital goods to support specific industries. These are periodically reviewed and can be altered or expire.
Because many levies, like the 7.5% Value Added Tax (VAT), are calculated on a base that includes the customs duty, any change in the CET rate has a compounding effect on the total landed cost.
A framework for preparing for CET changes
To prepare for tariff changes, agents and importers must meticulously audit their product classifications against the new tariff book and model the financial impact before preparing any customs declarations. Proactive analysis is the only effective defense against the uncertainty that follows a CET review.
Step 1: Conduct a full HS code audit
Do not assume your current HS codes are still valid. The first step is to obtain the newly gazetted CET and systematically check every single imported product against it.
Validate existence: Confirm that your 10-digit HS codes still exist in the new tariff.
Check for splits: If a code has been split, determine which of the new, more specific codes accurately describes your product. Choosing the correct one is critical, as they will likely have different duty rates.
Review descriptions: Read the chapter notes, section notes, and heading descriptions in the new tariff. The definitions may have changed in subtle ways that affect your product's classification.
Step 2: Model the financial impact
Once you have validated the correct HS codes, you must recalculate the expected duty for your key products. This allows you to update pricing, adjust budgets, and communicate with stakeholders. A simple before-and-after comparison can illustrate the impact.
Consider a hypothetical import of intermediate goods with a CIF value of ₦10,000,000 where the CET review increased the duty rate from 10% to 20%.
In this example, a 10-percentage-point increase in the base duty rate results in a total payable duty and tax increase of over 55%. This demonstrates the powerful cascading effect of a CET adjustment.
Step 3: Update systems and communicate
The final step is to institutionalise this new knowledge. Update your internal product databases, enterprise resource planning (ERP) systems, and any software used for creating quotes or pro-forma invoices. Crucially, communicate these changes to your procurement, finance, and sales departments to prevent incorrect pricing and budget overruns.
Preparing a declaration is the final step in a long process of commercial and logistical decisions. Decision support tools can help model these scenarios, providing foresight into how a customs risk engine will interpret a declaration based on the new tariff structure, before you commit to a lodgement.
The ECOWAS CET review is a recurring feature of the West African trade landscape. By treating it as a predictable, if complex, event and adopting a structured approach to analysis and preparation, you can mitigate compliance risks and maintain control over your import costs. Nohena prepares a lodgement-ready declaration and document pack; the licensed agent lodges.
FAQ
When does a new CET review take effect?
A new CET review takes effect on a specific date announced by the Federal Ministry of Finance and is implemented by the Nigeria Customs Service through an official circular. The new tariff rates are then enforced for all Single Goods Declarations (SGDs) accepted by customs on or after that effective date.
Can I contest a duty rate applied after a CET review?
Yes, you can contest a duty assessment through the formal dispute resolution mechanism provided by the Nigeria Customs Service. However, a successful challenge requires a strong, evidence-based argument, typically centered on proving the incorrect application of an HS code or a misinterpretation of the new tariff's legal notes, not simply disagreeing with the rate itself.
How does the CET review affect goods already in transit?
The applicable duty rate is determined by the tariff in force on the date your declaration (the SGD) is formally accepted by the customs system, not the date of shipment, bill of lading, or Form M opening. This means goods that are on the water when a new tariff takes effect will be assessed based on the new rates upon arrival and declaration.
Does the CET review impact VAT?
Yes, a CET review indirectly impacts the final VAT amount. VAT is calculated at 7.5% on the sum of the CIF value plus all other customs charges, including import duty, surcharge, CISS, and ETLS. Therefore, any increase in the base import duty from a CET review will automatically lead to a higher VAT base and, consequently, a higher VAT payment.