The hospital has its origins in the "Cheshire Lunatic Asylum" which opened on part of the site in 1829. The name of the facility changed to "County Mental Hospital" in 1921, to the "Upton Mental Hospital" on joining the
National Health Service in 1948, and then to the "Deva Hospital" in 1950. In 1993, the Royal Infirmary site was closed after its remaining departments were transferred to the Countess. The City Hospital, which had become a 120-bed geriatric unit, was closed in 1994 after its services were taken over by the Countess in 1991. In 2007, the Countess of Chester became the first hospital in the UK to completely ban
smoking for both workers and patients. In April 2014 a new two-storey wing was opened containing a state of the art 21 bed Intensive Care Unit on the first floor, replacing the old HDU and ITU wards. On the ground floor is an expanded endoscopy unit and the bariatric outpatients department.
Lucy Letby case and related investigations and arrests In August 2023, Lucy Letby, a
neonatal nurse who had worked at the hospital several years earlier, was found guilty on seven charges of murder and seven charges of attempted murder following a lengthy trial over the collapses and deaths of babies who were being cared for on the hospital's neonatal ward during 2015 and 2016. The jury concluded that Letby carried out the attacks by injecting babies with air or
insulin, overfeeding them and physically assaulting them with medical equipment. This explanation of the baby's deaths has been disputed by other medical experts, suggesting that Letby has been wrongly convicted and the deaths and collapses were the result of natural causes, with reportedly inadequate conditions and staffing levels on the neonatal ward also being a factor. The trust came under scrutiny following Letby's conviction as it was revealed management had protected Letby when consultants at the neonatal unit expressed their suspicions asked them to remove her from frontline duties. She was not removed from frontline duties until the summer of 2016, and remained on clerical duties until her initial arrest in July 2018. Hospital management did not report their suspicions to the police until May 2017, despite claiming that they were already having their suspicions about her conduct some 18 months earlier. The ward was downgraded following the final suspicious collapses and deaths over the summer of 2016, resulting in higher dependency babies no longer being treated there. On 4 October 2023, Cheshire Constabulary announced an investigation into
corporate manslaughter at the Countess of Chester Hospital. On 1 July 2025 three people who were "part of the senior leadership team" were arrested on suspicion of gross negligence manslaughter. They have been released on police bail, pending further inquiries. ==Services==