By law, employees in Germany are entitled to four weeks of vacation per year (“Jahresurlaub”); de facto, most enjoy at least five, if not six weeks.
When scheduling a business trip [to Germany], keep in mind that most offices in Germany are either closed during Christmas and New Year (December 24 to January 1) or operate on skeleton staff, and that during the summer, many people are on holiday, sometimes for up to three weeks in a row. Visiting companies during the months of June, July, and August can be a good opportunity to find people in an agreeable, rather relaxed mood; however, there’s also a fair chance that half the company will be on holiday, and people will be reluctant to agree to see you because not all relevant colleagues are there to join the meeting.Therefore, better keep yourself informed about public and school holidays in the federal states that you want to visit.
And, remember that Saturday is not a working day in Germany; many companies also close early on Fridays. While I, as a freelancer, sometimes meet foreign visitors on a Saturday, only on very rare occasions do I accept any meetings for Sundays. Sunday is sacred to (most) Germans, irrespective of whether or not they go to church.
When talking to decision makers in the manufacturing industries or in trade, it may happen that you are offered a meeting as early as 8 a.m.; especially in the manufacturing industry, many are reluctant to miss their (around 10 o’clock) breakfast break. With other industries, you can assume that office hours are generally from nine to five, and that people want to go for lunch sometime between 12 and 1 o’clock.