Short Answer Since the November 2023 immigration reform, changing jobs within the first twelve months of holding an EU Blue Card requires only a written notification to the immigration authority — not prior approval. The office may put your start date on hold for up to thirty days to review the new position, but if it stays silent, you simply begin working. What Most Expats Don't Realize You accepted an excellent corporate offer, switched companies, and never told the immigration office because nobody asked for any approval and everything seemed to work. Eighteen months later, your application for permanent residency stalled when the case worker discovered the unreported change sitting in your file as a compliance breach. You spent €1,500 on an immigration lawyer to clean up a record that one short letter at the time of switching would have kept spotless. What To Do * Send a written notification of your employer change to the immigration office before your first day, attaching the new contract. * Keep the proof of submission — if the office does not impose a hold within thirty days, you may start as planned. * "Hiermit teile ich der Ausländerbehörde meinen Arbeitgeberwechsel zum [Date] mit." (I hereby notify the foreigners office of my change of employer effective [Date].) — send this sentence with your new contract; it is a notification, not a request.