Who applies for the Belgian single permit – me or my employer?

The single permit application is employer-driven. The employer submits the file through the one-stop counter to the competent region for the place of employment, and the region and Immigration Office then assess it together.

This means your prospective employer plays a central role and must provide the employment-related documentation. As the worker, you will supply personal and identity documents, but you generally cannot lodge the single permit application by yourself without an employer behind it.