Austria +43
Number Format
Area Code: 1-4 digits (see note below)
Subscriber Number: 3-12 digits
Trunk Prefix: 0
International Prefix: 00
Note: Only Vienna (Wien) has 1-digit area code (+43 1); most geographic numbers have 4-digit area codes (with some 3-digit codes encountered). A few 2-digit area codes are assigned for special services such as private networks.
Area code information
2000-2001? National renumbering?
PTA AG reported that it will be required to establish a new numbering plan by 2000. No further word on whether or when this plan will be implemented. A European report from ESIS (Regulatory Developments Austria) mentions that Austria's telecom territory will be modified to 26 regions, with area codes assigned to each. However, an official decision on the structure of the new plan has not been reported yet. (Note - link to ESIS document seems to have disconnected at this time).
Other Information
Austrian telecom regulator is RTR, which as of 1 April 2001 replaced Telekom-Control. Their website has some information on elements of the current numbering plan. Also see RTR English reference.
Additional link info courtesy David Lindner.