
No. The temporary authorisation to stay must be requested before you enter Luxembourg; applications cannot be initiated once you are already in the country on another basis.
Luxembourg's self-employed route is built around a pre-entry authorisation. You request the temporary authorisation to stay from outside the country, through the Immigration Directorate or a Luxembourg diplomatic or consular mission, and only travel once it is granted.
This sequencing matters because trying to switch into self-employment from inside the country without that prior authorisation is not the intended path. If you are already in Luxembourg on another status and want to become self-employed, get specific advice on your situation, since the standard procedure assumes the authorisation is obtained before arrival.
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