In a statement yesterday, the Ministry for Housing, Communities and Local Government (MHCLG) said that Elliott will take on the role from 1 April, the day after her RTPI tenure comes to an end.
Elliott takes over as PINS chair from Sara Weller who held the position from August 2014 to September 2017.
Elliott will work with other non-executive directors on the advisory board to provide support to PINS chief executive Sarah Richards and the management team for a four-year period, MHCLG said.
Elliott said: "The Planning Inspectorate plays a vital function in the planning system and the future development of England and Wales.
"I am absolutely delighted to have been appointed to help with that task and look forward to working with Sarah Richards and her executive management team to continue to shape this renowned organisation".
Elliott also currently chairs the Oxford Joint Planning Law Conference Committee and sits on the National Infrastructure Planning Association policy council and the University of Warwick Estates Committee.
She was also a member of the Taylor Review into planning practice guidance and will become Patron of the Commonwealth Association of Planners from April.
The MHCLG announcement can be read here.