The Bala and Festiniog Railway was a 4 ft 8 1⁄2 in (1,435 mm), standard gauge, railway backed by the Great Western Railway (GWR) railway in North Wales. It connected Bala with Blaenau Ffestiniog.
The railway originally connected Bala with Llan Ffestiniog. It was incorporated on 28 July 1873 and opened on 1 November 1882. In 1883 the line was extended by converting the existing Festiniog and Blaenau Railway between Llan Ffestiniog and Blaenau Ffestiniog from 1 ft 11 1⁄2 in (597 mm) gauge to 4 ft 8 1⁄2 in (1,435 mm) standard gauge. The line terminated at Blaenau Ffestiniog (GWR) where until 1939 it connected with the Ffestiniog Railway to Porthmadog. At Bala Junction, the line connected with the Ruabon to Barmouth GWR line.
The Bala and Festiniog was vested in the Great Western Railway on 1 July 1910. On nationalisation in 1948 management of the line passed to the Western Region of British Railways.