IMPORTANT : Requests for the creation of social security numbers for insured non-EU, EEA and Swiss nationals are created by the General Department of immigration at the start of the application procedure for a residence or work permit. This procedure must be initiated by non-EU, EEA and Swiss nationals who want to work as residents or cross-border commuters in Luxembourg. Information on the procedure for applying for a residence or work permit is available on the following website: https://guichet.public.lu/en/citoyens/immigration.html
The 'DEMMAT' file contains the contact details of employees for whom the employer or their authorised representative does not yet have the full social security number, and makes a request to obtain it. If the employee is being employed in Luxembourg for the first time, the employer must provide a scan of an identity document with their request, using the 'CARTID' procedure.
Here are some instructions to help streamline the "DEMMAT – CARTID – MATRET – MATASS" procedure:
- Do not use full stops, commas, etc. to separate surnames and first names;
- Check that the data are correct (surname, first name, date of birth) before sending the file;
- Enter the full address (number, street, country, postcode, town/city) for each record;
- Attach the relevant 'CARTID' file (front and reverse) for each record;
- Check that the identity document is legible before scanning it;
- Check that the scan is legible before sending it using SOFiE via the 'CARTID' file;
- If a 'MATRET' erroneous record file is returned, please check the error code and do not resend the original 'DEMMAT' file as it is without checking that the data sent are correct.
DEMMAT file specifications
- The file is an uncompressed, ASCII-coded text file;
- Fields are separated by a semicolon (;);
- Each record ends with a carriage-return (0D hex) and a line-feed (0A hex).
File name when sent using SOFiE
DEMMAT.dta