Opinion of the Advocate General — ECLI:EU:C:1998:177
Date: 1998-04-30
Based on: Treaty establishing the European Economic Community (1957)
Subject matter: Taxation;Social security for migrant workers;Free movement of workers
Procedure: Reference for a preliminary ruling
Origin: Netherlands

Summary of the Judgment 
1. Freedom of movement for persons — Workers — Community provisions — Conditions of 
applicability — Exercise of the right to freedom of movement 
(EC Treaty, Art. 48; Council Regulation No 1612/68, Art. 7) 
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SUMMARY — CASE C-18/95 
2. Social security for migrant workers — Powers of the Member States to plan their social security 
systems — Limits — Compliance with Community law — Treaty rules on freedom of move­
ment for workers 
3. Freedom of movement for persons — Workers — Equal treatment — Higher social security 
contributions payable by workers who have transferred residence in the course of a year from 
one Member State to another — Whether permissible — Justification — None 
(EC Treaty, Art. 48) 
4. Freedom of movement for persons — Workers — Equal treatment — Workers who have trans­
ferred residence from one Member State to another — Social security contributions — Calcula-
tion 
5. Freedom of movement for persons — Workers — Equal treatment — National legislation 
requiring higher social security contributions from workers who have transferred residence in 
the course of a year from one Member State to another — Incompatible with Community law 
— Effects 
(EC Treaty, Art. 48) 
1. Article 48 of the Treaty and Article 7 of 
Regulation N o 1612/68 may be relied on 
by a worker against the Member State of 
which he is a national where he has resided 
and been employed in another Member 
State. 
Any Community national who, irrespec­
tive of his place of residence and his nation­
ality, has exercised the right to freedom of 
movement for workers and who has been 
employed in another Member State falls 
within the scope of the aforesaid provi­
sions. 
2. The fact that national rules concern the 
financing of social security does not exclude 
the application of Treaty rules, including 
those relating to freedom of movement 
for workers. 
While, in the absence of harmonisation at 
Community level, it is for the legislation 
of each Member State to determine the 
conditions governing the right or duty to 
be insured with a social security scheme, 
Member States must nevertheless comply 
with Community law when exercising that 
power. 
3. Article 48 of the Treaty precludes a Member 
State from levying, on a worker who has 
transferred his residence in the course of 
a year from one Member State to another 
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TERHOEVE v INSPECTEUR VAN DE BELASTINGDIENST PARTICULIEREN/ONDERNEMINGEN BUITENLAND 
in order to take up employment there, 
higher social security contributions than 
those which would be payable, in similar 
circumstances, by a worker who has con­
tinued to reside throughout the year in the 
Member State in question, without the 
first worker also being entitled to addi­
tional social benefits. Such a system for 
levying social contributions could deter a 
national of a Member State from leaving 
the Member State in which he resides in 
order to pursue an activity as an employed 
person, for the purposes of the Treaty, in 
the territory of another Member State and 
accordingly constitutes an obstacle to 
freedom of movement for workers. 
Such an obstacle may not be justified either 
by the fact that it stems from legislation 
whose objective is to simplify and coordi­
nate the levying of income tax and social 
security contributions, or by difficulties of 
a technical nature preventing other 
methods of collection, or by the fact that, 
in certain circumstances, other advantages 
relating to income tax may offset, or indeed 
outweigh, the disadvantage as to social 
contributions. 
4. When assessing whether the burden of 
social security contributions borne by a 
worker who has transferred his residence 
from one Member State to another in 
order to take up employment there is 
heavier than that borne by a worker who 
has continued to reside in the same Member 
State, all income relevant under national 
law for determining the amount of contri­
butions, including, as the case may be, 
income arising from real property, must 
be taken into account. 
5. Where national legislation requiring higher 
social security contributions to be paid by 
workers who transfer their residence in 
the course of a year from one Member 
State to another in order to take up employ­
ment there than those which would be 
payable, in similar circumstances, by 
workers who have continued to reside 
throughout the year in the Member State 
in question, without the former also being 
entitled to additional social benefits, is 
incompatible with Article 48 of the Treaty, 
a worker who transfers his residence from 
one Member State to another for that pur­
pose is entitled to have his social security 
contributions set at the same level as that 
of the contributions which would be pay­
able by a worker who has continued to 
reside in the same Member State. 
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