The latest SI designating the routes of Regional roads was published in 2006: the Roads Act 1993 (Classification of Regional Roads) Order 2006.

Routes of all regional roads in Ireland are defined by Statutory Instrument No. 188 of 2006, the Roads Act 1993 (Classification of Regional Roads) Order 2006; which specifies townlands, villages, towns, other settlements through which the route passes, as well as road names applied to route sections where applicable.

The government legislation that defines the R329, the Roads Act 1993 (Classification of Regional Roads) Order 2012 (Statutory Instrument 54 of 2012), provides the following official description:

The official description of the R112 from the Roads Act 1993 (Classification of Regional Roads) Order 2006 (Statutory Instrument 188 of 2006) reads:

The official definition of the R328 from the Roads Act 1993 (Classification of Regional Roads) Order 2006 states: