Lord Chief Justice Lord Judge is to retire as head of the judiciary next year, the Judicial Office said.
The 71-year-old President of the Courts of England and Wales has written to the Lord Chancellor to inform him of his decision and will officially step down at the end of September.
The move was announced "in view of public speculation" and the process to appoint his successor will begin early next year.
Lord Judge's replacement will be selected by a panel and is likely to be a Court of Appeal judge.
The Judicial Office said: "In view of public speculation, Lord Judge, Lord Chief Justice has decided to announce that he will continue in office until the end of September 2013, when he will retire.
"He has written to the Lord Chancellor to inform him of his decision.
"The process to appoint his successor as Lord Chief Justice of England and Wales will begin in early 2013."