The CAE – Economic Activity Code is used to classify the economic activity carried out by companies, sole traders and other entities.
Choosing the right classification is important not only for administrative and statistical purposes, but also because it may have tax, accounting and legal implications.
In addition, since 1 January 2025, the CAE Rev.4 – Portuguese Classification of Economic Activities, Revision 4 has been in force, replacing the previous CAE Rev.3. The transition to the new classification involved the reclassification of existing activity codes.
For this reason, in 2026, it is particularly important to check whether the CAE currently registered for your business accurately reflects the activity you actually carry out.
What is the CAE?
The CAE is a code used to classify the economic activities carried out by different entities.
This classification makes it possible to organize companies and other economic units according to the type of goods they produce or the services they provide.
The current CAE Rev.4 results from the revision of the European NACE classification and came into force in Portugal in 2025. The new classification introduced changes to the structure and codes of several activities, with official correspondence tables available between CAE Rev.3 and CAE Rev.4.
CAE codes consist of five digits, and an entity may have one main activity code and several secondary activity codes when it carries out different types of activity.
Why is it important to choose the right CAE?
Choosing a CAE should not be based solely on a generic description of the business.
The code should, as far as possible, reflect the activity that is actually being carried out.
An incorrect classification may create administrative and tax issues and, depending on the activity, may also have implications for specific obligations, licenses or eligibility for certain forms of support.
It is also important not to confuse the CAE with the tax framework. The CAE classifies the economic activity and does not, by itself, determine the entire tax treatment of a company or sole trader. Tax treatment also depends on other factors, such as the nature of the taxpayer, the type of income, the applicable VAT regime and the relevant tax regime.
Main and secondary CAE codes
A company carrying out several activities may have more than one CAE code.
For example, a company may have the operation of a restaurant as its main activity while also carrying out other activities that are properly classified under the CAE.
The main CAE corresponds to the entity’s main economic activity, while secondary CAE codes identify other activities that are also carried out.
The classification should therefore reflect the reality of the business rather than simply the activity that was initially planned when the company was incorporated.
CAE Rev.4: what changed from 2025 onwards?
One of the main developments that businesses should be aware of is the introduction of CAE Rev.4.
The new classification came into force on 1 January 2025. The Portuguese Tax and Customs Authority automatically updated taxpayers’ information, using different methods to convert the previous codes into the new classification.
This means that a company or sole trader that had a particular CAE under CAE Rev.3 may now have a different code under CAE Rev.4, without having directly requested that change.
For this reason, in 2026, we recommend checking the activity code currently registered for your business.
How can you check your CAE?
The official classification can be consulted through Statistics Portugal (INE) and SICAE, where you can find the CAE Rev.4 structure and the correspondence tables with the previous version.
For taxpayers carrying out an economic activity, the Portuguese Tax and Customs Authority also recommends checking the registration details available through the Portal das Finanças, in order to confirm that the registered activity code is correct.
Can the CAE be changed?
Yes. The CAE can be changed when the activity carried out by a business changes or when the registered code does not correspond to the activity actually being performed.
For companies and other legal entities, a change may be necessary, for example, when:
- the activity included in the company’s corporate purpose changes;
- the company starts carrying out a different activity;
- the registered CAE codes do not correspond to the activities actually being carried out.
If the new activity is already covered by the company’s corporate purpose, the CAE change can generally be made by submitting an activity change declaration through the Portal das Finanças.
If the new activity is not covered by the corporate purpose, it may first be necessary to amend the company’s corporate purpose with the Institute of Registries and Notary Services (IRN). Following the change, the information is communicated to the relevant authorities.
For individuals carrying out an independent activity, the activity code can likewise be changed through an activity change declaration submitted via the Portal das Finanças when they start carrying out a different activity or when the existing classification no longer reflects their actual activity.
Do I need to change my CAE following the introduction of CAE Rev.4?
Not necessarily.
The introduction of CAE Rev.4 resulted in the reclassification of existing activity codes, including through automatic processes carried out by the Portuguese Tax and Customs Authority.
Therefore, the introduction of CAE Rev.4 does not mean that every company must submit a new declaration simply because the new classification has come into force.
The important thing is to check the code currently assigned and confirm that it corresponds to the activity actually being carried out. If there is a discrepancy, an activity change declaration should be submitted with the correct codes.
What happens if my CAE is incorrect?
If the registered activity code does not correspond to the actual business activity, it is advisable to correct the situation.
An incorrect CAE may mean that the activity is incorrectly classified before the public authorities and may make it more difficult to ensure that specific obligations are properly identified.
In addition, certain activities are subject to specific rules, making it important to ensure that the declared activity accurately reflects the activity actually carried out.
The Portuguese Tax and Customs Authority and Statistics Portugal may also make official changes to the CAE where, within the scope of their respective powers, they identify that the existing code does not correspond to the activity being carried out.
How do I choose the most appropriate CAE?
The CAE should be chosen based on the activity actually carried out, rather than simply on the trading name of the business or a generic description of the services provided.
Before choosing or changing a code, it is important to consider:
- What is the main activity actually carried out?
- Are there other activities that are also carried out?
- Are the services or products offered correctly classified?
- Does the company’s corporate purpose cover the activities it intends to carry out?
- Does the CAE registered with the Portuguese Tax and Customs Authority and SICAE correspond to the business’s current activities?
If you are unsure, we recommend seeking advice from a certified accountant or consulting the official classification provided by Statistics Portugal.
CAE and taxation: what is the connection?
The CAE may be relevant to the tax framework, but it is important not to oversimplify the relationship between the two.
The CAE does not, by itself, determine how much tax a company or sole trader will pay.
Taxation depends on the taxpayer’s overall circumstances and the characteristics of the activity, including the VAT regime, the applicable personal or corporate income tax regime and other relevant tax rules.
Nevertheless, correctly identifying the activity is essential to ensure that the applicable tax framework and reporting obligations are assessed based on the actual circumstances of the business.
In summary
Choosing the right CAE should be regarded as an important decision when starting a business and as something that should be reviewed whenever the business evolves.
In 2026, this issue deserves particular attention due to the introduction of CAE Rev.4 in 2025 and the resulting update of activity codes.
If your company has changed its activities, started providing new services or you simply want to confirm that the CAE currently registered is correct, it is important to check the information.
Do you have questions about your company’s CAE or the classification of your activity? Get in touch with our accounting team. We can help you assess your business activities and check whether your registered classification is up to date and appropriate for your business.