This contend is a translation from the website http://www.ukaachen.de/fuer-aerzte/im-notfall.html

Please check the original website, to assure whether there have been any changes.

The hospitals in Aachen have have emergency service during night time at different days of the week.

5pm to 8am:
Monday: Luisenhospital Boxgraben 99, Tel:
Tuesday: Uniklinik RWTH Aachen, Pauwelsstraße Tel:
Wednesday: Franziskushospital, Lütticherstr. 110 Tel:
Thursday: Marienhospital, Abteistr. 1 Tel:
Friday: Uniklinik RWTH Aachen, Pauwelsstraße Tel:

Saturday 8am until Monday 8am:
1st   Weekend of the month: Luisenhospital
2nd Weekend of the month: Uniklinik RWTH Aachen, St. Franziskus-Krankenhaus
3rd  Weekend of the month: Uniklinik RWTH Aachen
4th  Weekend of the month: Marienhospital
5th  Weekend of the month: Uniklinik RWTH Aachen

At other times of the day all the hospitals have emergency service.