For winter semester, you should apply between early June and 15th of July (final deadline) of the year in question. For summer semester, you should apply between December of the previous year and 15th of January (final deadline) of the year in question. Applications need to be sent to the International Offices of individual universities, to “uni-assist”, or to a central service called “hochschulstart.de,” depending on the respective study programme.
Note: Some universities have different application periods and deadlines. This especially holds for academies of music, art etc., and for international study programmes! Please contact the university of your choice as early as possible to find out what the exact application dates are and when courses begin.
Usually, there are no entrance exams at German universities (except for music, art etc.). Students are admitted after evaluating their application documents. In many study programmes, the open places are distributed among the best applicants ("zulassungsbeschränkte Studiengänge/Fächer"), but there is also study programmes which generally accept all applicants ("zulassungsfreie Studiengänge/Fächer"). But even in that case, you will usually have to apply by the regular dearline if you do not have a German Abitur.
Depending on the institution and the study programme, there is three different application procedures.
Application directly at the university
You have to apply directly at the university which checks if all you documents are valid.
Uni-assist is an association of more than 125 German higher education institutions. You will find a list of its members here. Uni-assists checks all application documents for the university, decides if the applicant is formally eligible and sometimes also asks for additional material. If you application meets all requirements, uni-assist forwards it to the respective universities.
Applications in medicine, dentistry, veterinary medicine and biology are administered by a central agency called hochschulstart. Applicants can name universities they prefer, but eventually the agency decides if and where you get a place. This procedure is highly complex and we recommend to consult personally at the DAAD Information Center.