Born in Macerata on 12 February 1958, he graduated in economics and business at the University of Perugia.

Accountant and auditor, he is managing partner of Simonelli Associati, a tax law firm based in Milan.

Simonelli is Chairman of the Board of Statutory Auditors of Sisal Group S.p.A. and Mediaset Italia S.p.A., and Standing Auditor of Recordati S.p.A. and F2i Sgr.

Since April 2018, Standing Auditor of Arnoldo Mondadori Editore S.p.A.