Borgarhreppur was formerly a rural parish (hreppur) in Mýrasýsla county, west Iceland, named after the ancient farm and church estate Borg á Mýrum which was occupied by Skallagrímur Kveldúlfsson, one of Iceland's original settlers.
Hraunhreppur was formerly a rural parish (hreppur) in Mýrasýsla county, west Iceland.
Norðurárdalshreppur was formerly a rural parish (hreppur) in Mýrasýsla county, west Iceland.
Stafholtstungnahreppur was formerly a rural parish (hreppur) in Mýrasýsla county, west Iceland, described as a "typical farm parish".