a new numbering plan was introduced on 3 may 2010. since then new landline phone numbers have a standard length of 11 digits, which includes the area code but omits the trunk prefix of 0. area codes remain as they are and are still variable in length. exceptions to the 11 digit rule are the four cities of berlin, frankfurt, hamburg and munich, which are the only cities with two digit area codes and require only 10 digit numbers so as not to exceed the maximum length of 8 digits for a subscriber number.