The constituency was a new creation of the Boundary Commission for Wales and was based on the existing Conwy seat. It was centred on Llandudno, Conwy town and associated suburbs such as Deganwy and Penrhyn Bay, along with the Conwy Valley. The other main component of the former Conwy seat, Bangor, was removed to the Arfon constituency.
The name Aberconwy was chosen partly to avoid confusion between the former Conwy parliamentary seat (which, confusingly, had been the name first proposed by the commission for the new seat), the existing county borough, town council and ward name. The seat was coterminous with the old Aberconwy district, abolished in 1996, and thus the name was thought to be a natural one with which to name the new constituency. Bangor, the main Labour voting area of the former Conwy constituency, is no longer within the constituency, whereas the more Conservative areas such as Llandudno and Conwy itself are retained. The constituency is diverse, combining Welsh-speaking rural areas, English-speaking coastal dwellers, many affluent suburbs, pockets of relative poverty, seaside resorts such as Llandudno and more industrial areas such as Llandudno Junction. In many ways the new Aberconwy seat resembled its neighbour Clwyd West (the other seat covering Conwy County Borough) to a large degree, as both seats have a similar social profile and, as seems likely, a similar voting pattern.
The wards of Conwy County Borough that were incorporated into the Aberconwy seat were: