About us


Mantell, Rossi & Company is a boutique accounting firm based in Watchung, New Jersey. 

Founded in 1952, Mantell, Rossi & Company is a local firm, small by design.  Founded on the key principles that our clients mean everything to us and their success is our bottom line, we tailor each solution to your individual client needs. 

American Institute of Certified Public Accountants

New Jersey Society of Certified Public Accountants

New Jersey Better Business Bureau



Beyond providing tax solutions, the company specializes in consulting, financial advisory, mergers and acquisitions, operations and strategy to select clients.  The company has grown in the past 60 years through passion for our clients and craft, and trust and confidence in our business acumen.


JOHN C. ROSSI brings more than forty years of experience as an accountant and seasoned professional in international business.  

John is the co-founder and Chief Executive Officer of Mantell, Rossi and Company and is responsible for all aspects of the company’s business. Under John’s leadership, Mantell, Rossi and Company is one of the leading boutique small premier financial planning and certified public accounting firms in the tri- state area.

Prior to founding Mantell, Rossi and Company in 1986, John served as the Chief Financial Officer of Elm Securities, Inc. a boutique investment bank specializing in private placements overseas. Prior to Elm Securities, Inc, John served as Chief Financial Officer of Villeroy and Boch, USA, in charge of all US financial operations and information processing functions. John was also the Manager of Planning and Financial Analysis for the Card Division at American Express began his career at Price Waterhouse and Revlon.

In addition, John serves as a member of Rotary Club of Watchung, raising funds for worthwhile non-profit causes, and has, in the past performed pro bono work for the Somerset County Park Commission Foundation and the Watchung Arts Council. . John is a member of the American Institute of Certified Public Accounts, New Jersey Society of Certified Public Accountants.. John holds a B.A. from Gettysburg College, and a C.P.A. in the State of New Jersey.