Heartlands Interchange is M8 Junction 4A, a relatively new junction serving the Heartlands development at Whitburn. It was entirely funded by the private sector, the first motorway junction in Scotland to be so funded. Work started summer 2012 and opened on the 14th of September 2013. The junction is a dumbbell layout serving an unclassified road which passes over the top of the motorway and heads south to meet the B7066 and B7069 at a roundabout on the edge of the town. On the way, it passes through two more roundabouts built to serve the new industrial estate / business park development. One of the first occupants of this new development is the Heartlands services.
Three of the four sliproads are single lane, but the eastbound offslip has two lanes as it reaches the roundabout. The over bridge is fully dualled, despite the only other exit being a farm road to Balgornie Farm, whose original bridge was removed to make way for the new west facing slips. On the south side, the dual carriageway curves away to the southwest, with an additional stub to the south east awaiting future development.
