The section of line between Hereford and Moorhampton opened for goods traffic on 24 October 1862, with the section to Eardisley following on 30 June 1863. Further extensions of the line reached Hay-on-Wye on 11 July 1864 and Three Cocks Junction on 1 September 1864. Passenger train service from the HH&BR's Moorfields station in Hereford to Eardisley commenced on 30 June 1863 and passenger traffic to Hay began on 11 July 1864. The line extension to Brecon was opened for goods traffic on 1 September 1864 and for passenger trains on 21 September 1864.
The HH&BR attempted to amalgamate with the B&MTJR, but the Act of 5 July 1865 was ruled to be improperly processed and therefore illegal. The MWR therefore worked the line from 1 October 1868. The Midland Railway Company (MR) took over the HH&BR from 1 October 1869, leasing the line by an Act of 30 July 1874 and absorbing the HH&BR in 1876. The MR closed Hereford Moorfields station on 1 April 1874, thereafter trains used Hereford Barr's Court railway station (Hereford railway station from 1893). The MR was absorbed into the London, Midland and Scottish Railway (LMSR) on 1 January 1923. The line was closed, along with other lines serving Brecon, in 1962 - shortly before publication of the Beeching Report.