What is a personal representative?
Personal representative is the collective term for whoever is legally responsible for administering an estate — an executor where there is a will, an administrator where there is not. HMRC, courts and financial institutions use it as the umbrella term covering both roles.
The distinction matters mainly in timing and authority. An executor's powers come from the will and exist from the moment of death; an administrator's powers come from the grant and exist only once it is issued.
The duties, once acting, are substantially the same: collect in the estate, pay what is owed, distribute correctly, and keep proper accounts for the beneficiaries.
You will see the term used in HMRC correspondence and on inheritance tax forms, where it avoids having to specify which of the two roles applies.