She is due to appear at Warrington Magistrates’ Court today to face the charges, a spokesman for Cheshire Police said.
Letby, of Arran Avenue, Hereford, was arrested for a third time on Tuesday as part of the investigation into deaths at the hospital, which began in 2017.
Police launched a probe after the hospital raised concerns at the high number of deaths between March 2015 and July 2016 – which were said to be 10 per cent above average.
An internal inquiry was undertaken when medics found premature babies had died following heart and lung failure.
Letby’s friends and family said at the time they were adamant the “awkward but kind-hearted” neonatal nurse was innocent.
A force spokesman said: “The Crown Prosecution Service has authorised Cheshire Police to charge a healthcare professional with murder in connection with an ongoing investigation into a number of baby deaths at the Countess of Chester Hospital.
“Lucy Letby, of Arran Avenue, Hereford, is facing eight charges of murder and 10 charges of attempted murder.
“The charges relate to the period of June 2015 to June 2016.”
On Tuesday, police said parents of all the babies involved were being kept fully updated on developments and were supported by officers.
Letby was arrested by police in 2018 and again in 2019 but was bailed pending further inquiries.
Following her previous arrests, her home in the Blacon area of Chester was searched by police.
In a 2013 interview with the Chester and District Standard newspaper, the nurse said she cared for babies requiring various levels of support.
She had worked at the unit as a student nurse during three years of training before qualifying as a children’s nurse at the University of Chester in 2011.
Letby said she started working at the unit after graduating.
Yesterday, police said specially-trained officers are working with families after Letby’s re-arrest.
“A dedicated team of detectives have been working extremely hard on this highly complex and very sensitive case doing everything they can as quickly as they can to identify what has led to these baby deaths and collapses,” said Detective Chief Inspector Paul Hughes, who is in charge of the investigation.
“Parents of all the babies have been kept fully updated on this latest development and they are continuing to be supported throughout the process by specially trained officers.
“This is an extremely difficult time for all the families and it is important to remember that, at the heart of this, there are a number of bereaved families seeking answers as to what happened to their children.”