It is managed by the Betsi Cadwaladr University Health Board.

The facility has its origins in the Holyhead Workhouse Infirmary at Black Bridge on the north-west part of Salt Island which opened in 1852.

[1] Patients were transferred from Stanley Sailors' Hospital when it closed in 1987.

[2] The current facility was built on Penrhos Beach Road on the south-east part of Salt Island, just under a mile from the old hospital, and opened as Ysbyty Penrhos Stanley in 1996.

[3] A four-bed hospice unit was created in an unused ward within the hospital in 2019.