Norwegian Postal Codes are 4-digit codes, known in Norwegian as postnummer (literally "post number"). Posten, the Norwegian postal service, makes small modifications to the postal code system each year. In 1999 Posten made considerable changes to the postal codes in Norway.
Since 18 March 1968 Norway has used a four-digit system: postnummersystemet. The numbers start at 00 and increase with the distance from the capital city Oslo. The highest post numbers are found in the county of Finnmark, near the Russian border, where they start with 95–99. The lowest post code in use is 0001 (Oslo), the highest 9991 (Båtsfjord).