About Us
Our Firm
The predecessor of POSI, which is a certified public accountant corporation, was established in 1992. Later, it split into three separate corporations specializing in certified public accountant services, accounting outsourcing services, and payroll-related services, all with the aim of improving efficiency. POSI was created in response to clients that needed services beyond the scope of what a CPA firm could provide. Since our founding, it has been our goal to build long-term relationships with our clients. We act as your outside partner, handling essential business functions while allowing you to focus on the core competency of your business.
Our Core Service Areas and Business Support in the U.S.
Accounting
Services
Payroll
Services
Tax & CPA Services
Our Features
Outsourcer specializing in accounting & payroll
Formerly an accounting firm: Comprised of accounting and tax professionals and CPAs with experience in various industries
Pulling for Your Success
Small businesses must focus on generating revenue and rarely have the resources for the specialized employees they need. As a result, small businesses often end up relying on inadequate service providers. We offer a solution to this dilemma: outsourcing. Outsourcing has become one of today’s most powerful management strategies. Outsourcing the non-revenue generating aspects of your business will give you an edge that will ensure your business can compete in today’s rapidly evolving marketplace. Outsourcing enables you to spend your valuable time on the profitable aspects of your company. You can invest your energy and resources efficiently to secure the future of your business. Do what you do best and outsource the rest. POSI staff are highly trained to process data and manage accounting systems. We understand the importance of consistency and accuracy. Ever focused on our mission, we do not produce or sell company products. Our specialty is accumulating data, processing information, and reporting on business activity.
Our vision is to inspire confidence in professionals so they can succeed in the US and Japan. Our mission is to provide timely and valuable services while taking ownership of our customers’ needs. Our greatest reward is appreciation from our clients. At POSI, empathy is a priority, internally and externally, and this enables us to provide the best possible service for our clients. In anticipation of ongoing changes in technology and client needs, we are flexible and proactive, continually updating our service offerings as needed.
Yoshimasa Hotta, CPA
Chief Executive Officer
Our Members
Yoshimasa Hotta, CPA
Chief Executive Officer
In 1990, after having worked as a senior manager for Deloitte, Mr. Hotta founded Hotta Liesenberg Saito LLP, which grew to become a world-renowned CPA firm. In 2011, he joined POSI with the vision of creating more personalized and empathetic services for clients. He is a certified public accountant registered in California, New York, and New Jersey. He is also a licensed investment advisor representative (IAR). Mr. Hotta enjoys gardening and grows vegetables and fruit trees in his spare time.
Mayet Alegria
President
Having worked for Hotta Liesenberg Saito LLP, Shaw & Shaw, and Zurich Payroll Solutions, Ms. Alegria brings a wealth of account and tax management experience to her role as president of POSI. She incorporated POSI and hired the initial team, establishing an employee-focused corporate culture that persists to this day, nearly 20 years later. In her free time, Ms. Alegria enjoys a close relationship with her family. Together, they actively support the Samaritans Purse charity by donating school supplies, toys, shoes, and more to less fortunate children.
Masaki Shimomura, CPA
President of Accountancy
After working at two Japanese accounting firms in New York in the 90s, Masaki founded Shimomura & Co., CPAs in 2002. He grew his firm to a multi-million-dollar firm with offices in New York, Los Angeles, and Tokyo. He served a wide range of international clients, including trading companies, auto parts manufacturers, general manufacturing, distributors, and advertising agencies. He is a certified public accountant registered in California and New York.
In January 2024, his firm joined POSI to utilize its global resources to meet the increasing needs of complex multinational corporations.
Masaki enjoys sightseeing, and one of the things on his bucket list is to visit all the US national parks.
Leaders
Senior Manager
Senior Manager
Manager
Manager
Marketing Director
Senior Manager
Senior Manager
Manager
Senior Manager
Senior Manager
Jacqueline Ramon
Manager
Senior Manager
Director
Director
Law Offices of Donald A. Barnes, PLLC
Law Offices of Donald A. Barnes, PLLC provides legal services to POSI regarding U.S. Federal income tax matters on an as-requested basis if mutually agreeable on a case-by-case basis.
Past Employment Positions:
- Acting assistant to the Commissioner of Internal Revenue (administration of President George H.W. Bush)
- Internal Revenue Service, Office of Chief Counsel (Income Tax & Accounting division), Washington, DC
- Partner, National Tax Office of BDO Seidman, LLP, a CPA firm
- Law Practice, Baker & Hostetler (associate and partner), Denver, Colorado
Professional Associations and Memberships:
- Member, District of Columbia Bar Association
- Chairman, AICPA Tax Legislation and Policy Committee, 2004-2005
- Member, Independent SALT Alliance
Los Angeles HQ
Professional Outsourcing Solutions, Inc.
Payroll Outsourcing Solutions, Inc.
POSI Accountancy, P.C.
Address：
970 W. 190th Street, Suite 920
Torrance, CA 90502, USA
Phone：
+1 (310) 243-1100
Fax:
+1 (310) 243-1106
Email：
contact@posiusa.com
Business hours：
Daily: 8:30 am – 5:30 pm
Closed: Saturdays and Sundays
Branch
420 Lexington Avenue, Suite 300
New York, NY 10170
Phone: (646) 452-8033
9425 Waterstone Blvd., Suite 140-146
Cincinnati, OH 45249
Phone: (513) 444-2136
1441 Kapiolani Blvd., Ste. 1115 – PMB#1005
Honolulu, HI 96814
Phone: (808) 808-4540
Pride Outsourcing Solutions International, S.C.
Attention: Yuki Murakami
Presa la Angostura #23, Piso 1
Col. Irrigación, 11500, CDMX
Phone: +52 (55) 5250 5537 Ext.104
POSI, Inc.
Attention: Madoka Ouchi
1-5-1 Otemachi, East Tower 4th Floor
Chiyoda-Ku, Tokyo 100-0004
Phone: +81-3-5219-1333
Fax: +81-3-5219-1201
POSI Companies
These three entities work together to provide services. We provide our accounting services through Professional Outsourcing Solutions, Inc., and payroll services are delivered by Payroll Outsourcing Solutions, Inc. Tax returns and attestation services are handled through POSI Accountancy, P.C., a California-based CPA firm. These are legally independent business entities and do not share any liability with one another.