Prior to industrialisation, most of the land was owned by one of the great families of Glamorgan with Treorchy coming under the domain of the Marquess of Bute Estate.

[3] The first deep mine in Treorchy was sunk in the 1860s by David Davies of Llandinam who would later own the Ocean Coal Company.

[4] The initial development of the town was linear, based on the main road through the valley, but by 1875 a grid pattern of streets was emerging.

[6][7] A 2018 review of electoral arrangements by the Local Democracy and Boundary Commission for Wales would see Treorchy's representation reduced from three to two councillors.

[9] Treorchy became a commuter village, with the working population seeking employment in the larger towns and cities nearby, such as Cardiff and Bridgend.

[11] The Guardian reported that the town has grown its chamber of trade from 30 members to 120, and nearly 30 businesses have opened in recent years, producing an occupancy rate of 96%.

The A4061 over the Bwlch y Clawdd Pass leads to Bridgend, via the Ogmore Vale, and to Maesteg and Port Talbot.

The route on the A4058 southwards follows the valley's course to Llwynypia, Tonypandy, Porth and Pontypridd to join the A470 for Cardiff.

Treorchy railway station is located on the Rhondda Line, with regular services to Treherbert and Cardiff Central run by Transport for Wales.

Treorchy is served by buses operated by Stagecoach running to Blaenrhondda, Blaencwm, Treherbert, Tonypandy, Porth, Pontypridd and Caerphilly.