Hamburg is 1 hour ahead of Reykjavik
Best overlap: 8:00 AM to 5:00 PM in Reykjavik is 9:00 AM to 6:00 PM in Hamburg.
Both offices are open during 8:00 AM to 5:00 PM Reykjavik time, which is 9:00 AM to 6:00 PM in Hamburg. Hamburg is 1 hour ahead of Reykjavik, and with 9 hours of overlap you can even run back-to-back calls without stepping outside business hours. The window above shifts seasonally: Hamburg keeps daylight saving while Reykjavik ignores it.