Telephone numbers in Sweden

In Sweden, the area codes are, including the leading 0, two, three or four digits long, with larger towns and cities having shorter area codes permitting a larger number of telephone numbers in the eight to ten digits used (including the leading '0'). Before the 1990s, ten-digit numbers were very rare, but they have become increasingly common because of the deregulation of telecommunications, the new 112 emergency number (which required change of all numbers starting with 11), and the creation of a single area code for the Greater Stockholm area.

Source: Wikipedia — Telephone numbers in Sweden (CC BY-SA 4.0)