A 150 kilometres (93 mi) track between Chittagong and Comilla was opened to traffic in 1895.

The line was extended to Tinsukia in 1902 and it was also connected to Dibru-Sadiya Railway in 1903.

[5][12] and the portions about 2,600 km long which fell within the boundary of erstwhile East Pakistan was named as Eastern Bengal Railway, the control remaining with the central Government of Pakistan.

[17][18] The Indian part of ABR was converted to 1,676 mm (5 ft 6 in) broad gauge in 1990s to 2010s.

The Bangladesh part is under conversion to 1,676 mm (5 ft 6 in) broad gauge.