Do German universities send out all master's rejections in one batch, or on a rolling basis during the admission round?

Your rejection timeline depends entirely on whether your program is open admission or capacity restricted. There is no single rule across Germany, so the type of program you applied to tells you what to expect.

Rolling Versus Batch Rejections

What Happens Between Rounds

For restricted programs, the university first ranks every qualified applicant, then sends acceptances to the top candidates. Only after seeing how many accepted students decline their offers does the university release rejection letters to the remaining waitlist, so a late rejection does not mean your file was weak.

My Advice

Check whether your program is marked open or restricted on the university's admission page, since that single detail tells you how long to expect to wait. If your program is restricted, do not panic before the waitlist rounds finish, and keep a backup application moving in parallel just in case.