A ‘no-cost SNE’ refers to a seconded national expert at the European Commission, an EU agency or other EU institution where the receiving institution does not have to pay any of the expenses associated with “regular” SNEs like the Daily or Monthly Subsistence Allowances. However, if no-cost SNEs go on missions on behalf of the contracting institution, they will receive the same mission allowances and support as other staff of the institution.
Article about Seconded National Experts and SNE allowances in EU institutions.
Official cohabitation counts as family and entitles you to the allowance. In case it’s relevant to anyone, same sex couples…