SH 29A was gazetted in 2015 and covers the former section of SH 29 east of the roundabout with SH 36/Route K. SH 29A starts at a roundabout interchange with SH 2. The highway crosses the East Coast Main Trunk Railway and passes Baypark Stadium. From here, SH 29A becomes a four lane dual carriageway until just before it crosses the Maungatapu Bridge, past Rangataua Bay. The highway travels in a wide cutting through Maungatapu, and Taipari Street crosses it on a bridge. Then SH 29A arrive at the signalised roundabout at Hairini, so traffic wishing to stay on the highway must turn either left or right depending on their direction of travel. It then travels straight across another signalised roundabout at Welcome Bay, before travelling through four roundabouts within 5 km, eventually terminating with SH 29.