What are Werktage in Germany?

In Germany, work days (Werktage) usually mean Monday to Saturday, excluding public holidays.1 This is true for traffic signs, mail delivery, and most other situations.

This is different from business days (Arbeitstage), which usually mean Monday to Friday, excluding holidays.

On apartment leases, it means Monday to Friday, excluding official holidays.2

Sources and footnotes
  1. generali.de, Wikipedia 

  2. anwaltauskunft.de