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# When is the fixed rate advantageous?

The fixed rate is advantageous when there is a significant difference in salary between the two spouses.

* If one spouse earns income in Luxembourg and the other abroad (Belgium, for example), the income from Luxembourg must be higher than the income from Belgium. 
* If this is not the case, opting for the Luxembourg rate would not be advantageous, as it would only increase your tax rate! In this case, it is better to remain in tax class 1.