Hannah Doody is set to take over the top job from Ged Curran who announced he was stepping down in January after 17 years at the helm.
Ms Doody has been director of community and housing at the council for the past four years.
She will take up her new role on July 7 after the appointment is confirmed at a full council meeting.
The salary for the job is set to be between £180-200,000.
Council leader, Mark Allison, said: “We are delighted to appoint Hannah following unanimous cross-party agreement. Under her direction, our adult social care and community services have gone from strength to strength, and she has continued to cement her leadership reputation during the pandemic, both with our partners in Merton and as the London lead on resilience on behalf of the association of Adult Social Care Directors (ADASS).
“I would also like to again pay tribute to Ged Curran, who has served the borough for 17 years and successfully guided us through a series of improvements including schools and local leisure and regeneration, while maintaining and protecting our key services in the face of significant budget pressures.”
Ms Doody said she is “immensely proud” to be taking on the job.
She added: “Merton has built a fantastic base to move forward from, and has set standards in London for improving education, support for vulnerable residents and protecting vital community services in the face of budget deficits.
“I look forward to working with councillors, staff and our partners and local residents to develop the next phase of our improvement journey across the borough.”
Before coming to Merton Council, the incoming chief executive held senior roles at Greenwich and Kingston councils.
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