CF91 Cardiff / Caerdydd Postcode district CF91: 1 named streets and 14 live postcodes, in Cardiff. Streets Penarth Road, Cardiff / Caerdydd Postcodes CF91 1XN CF91 5AB CF91 5AD CF91 5AE CF91 5AF CF91 5AG CF91 5AH CF91 5AL CF91 5AN CF91 5AP CF91 5AQ CF91 5AS CF91 5AT CF91 5AU Source: ONS Postcode Directory (live postcodes only) and OS Open Linked Identifiers for the streets.