International mobility continues to grow in 2026, leading more and more people to move abroad for professional or personal reasons.
However, changing your country of residence is not just a logistical matter — it involves significant tax implications that, if ignored, can lead to serious problems.
At FA ACCOUNTING, we support international relocation processes and have observed that the most common mistakes are still related to determining tax residency.
What happens tax-wise when moving abroad?
When moving to another country, several important tax changes may occur:
- Change in tax residency;
- Becoming subject to taxation in a new country;
- Possibility of having tax obligations in two countries simultaneously.
Tax residency: the key factor
In 2026, tax residency continues to be determined by three main criteria:
- Physical presence in the country;
- Availability of a permanent home;
- Center of economic and personal interests.
An incorrect assessment of these factors may result in double taxation or non-compliance.
Common risks
- Double taxation on the same income;
- Failure to notify tax authorities;
- Improper maintenance of tax residency in Portugal.
Obligations when leaving Portugal
- Update your tax address;
- Notify the change on the Tax Authority Portal;
- Close your activity, if applicable.
Obligations when entering another country
- Register as a taxpayer in the new country;
- Assess taxation on earned income;
- Comply with local tax rules.
Double taxation agreements
Portugal has several international agreements that allow:
- Avoiding double taxation;
- Defining which country has taxing rights;
- Reducing the overall tax burden.
Best practices
- ✔ Plan your tax situation before moving
- ✔ Evaluate tax impact in both countries
- ✔ Keep proper documentation
- ✔ Seek professional advice
How FA ACCOUNTING can help?
- Tax residency analysis;
- International tax planning;
- Support during relocation;
- Mitigation of tax risks.
Move abroad with tax peace of mind
📞 Contact us before making decisions to ensure a smooth and efficient transition.
Note: Informational content based on legislation in force in 2026.
Did you like this article?
Share it with anyone considering moving abroad.