183 days rule obstructing cross-border mobility

  • Giulia Brustia profile
    Giulia Brustia
    13 February 2020 - updated 1 year ago
    Total votes: 0
Martin Unfried
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Martin Unfried - Oost-Vlaanderen Province - Euregio Scheldemond, BE-NL


The Advice Case „183 days rule obstructing cross-border mobility“ submitted by the Oost-Vlaanderen Province under the initiative b-solutions was consulted by Martin Unfried, a legal expert with sound knowledge of cross-border matters who helped the applicant to better identify the obstacles preventing the employment of cross-border workers in the North Sea Port.

The expert concluded that the employment of frontier workers is limited by the complex provisions regulating income tax included in the Belgian-Netherlands Tax Treaty (2001). Furthermore, a lack of coordination between tax rules and social security rules is also observed, so much that the provisions are even calculated on the basis of different time frames.


The solution proposed for both obstacles by Martin Unfried envisages the introduction of amendments to the Belgian-Dutch Tax Treaty.

This will help creating a special regime for cross-border income taxation and will facilitate the harmonization of the time frame for the social security provisions.


To know more about the analysis of this Advice Case, download the full report of the expert.


The information here provided have been developed in the framework of b-solutions, an initiative of the European Comission’s DG REGIO managed by the Association of European Border Regions (AEBR).

The reports here included are the result of a consultation provided by legal/cross-border cooperation experts on obstacles of a legal or administrative nature– referred to as Advice Cases - selected in the framework of the II Call for Proposals of the initiative b-solutions