Idd is a parish and former municipality in Halden, Østfold county, Norway.
The parish of Id was established as a municipality January 1, 1838 (see formannskapsdistrikt). The rural municipality was (together with Berg) merged with the city of Halden January 1, 1967. Prior to the merger Idd had a population of 7,213.
The municipality (originally the parish) is probably named after an old name of the vicarage. The meaning of the name is, however, unknown.
Until 1918 the name was written Id.
adv. (context Internet slang English) (abbreviation of indeed English)