The CPS added that Mr Thelwell has the right to a fair trial.
A 23-year-old student who was arrested by police after eggs were thrown in King Charles and Camilla's direction, has been charged with public order offence. The King and Queen Consort carried out an engagement in northern England in November.
Patrick Thelwell, a University of York student will appear at York Magistrates' Court on January 20, BBC reported.
Video on social media showed four eggs flying past the British monarch and his wife and smashing on the ground as they arrived for a traditional ceremony in York. They appeared to be unmoved by the incident and carried on with the engagement.
Police officers rushed in to drag away a protester who was shouting slogans. Others in the crowd jeered him, and chanted: "God save the king".
King Charles' security team temporarily directed the man away from the crowd outside Luton Town Hall. He was then transported to another area and the King started shaking hands with the crowd again.
During his visit to the Bedfordshire town, the monarch also visited the Guru Nanak Gurdwara and the town hall, as per The Guardian report.
Announcing the charges in Mr Thelwell's case, Nick Price, head of the CPS Special Crime and Counter Terrorism Division, told BBC, "The CPS has authorised North Yorkshire police to charge Patrick Thelwell with threatening behaviour contrary to Section 4 of the Public Order Act 1986.
"This follows an investigation by police into an incident in which eggs were thrown at HM The King in York on November 9 2022." The CPS added that Mr Thelwell has the right to a fair trial.
The royal family has experienced egg protests before - in 2002 when Queen Elizabeth II visited Nottingham, eggs were thrown at her royal car. In 1995, anti-British protesters threw eggs at the now King while he was on a walkabout in central Dublin.