Keystone Tax Services, the accounting firm of Joseph Oommen, was established in 1995 to provide efficient, expert solutions to businesses and individuals. Our primary services include accounting, taxation, and business consulting. We also offer a host of specialty services to cater to the unique needs of our clients.

Our accountants serve a wide range of individuals, corporations, partnerships, and non-profit organizations and are experts in accounting issues and tax laws that impact our clients. We are committed to providing a complete range of professional tax and accounting services, at affordable fees. We pledge to create an environment that will cause every one of our clients to view us as a trusted business advisor.

Contact us to schedule a complimentary, no-cost, and no-obligation initial consultation with Joseph Oommen.

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Meet Joseph

Joseph Oommen graduated from University of Dallas, TX in 1993 with a Bachelor’s degree in accounting, and immediately joined the accounting department of a leading industry. After many years of private industry accounting experience, he started his own firm, and has been serving the Philadelphia and Bucks area since 1995. Today, his firm, Keystone Accounting & Tax Services offers expert accounting, tax, and business consulting services to thousands of individuals and small businesses. In addition to his expertise, Joseph Oommen prides himself on delivering affordable services in a timely manner with a personal touch. That’s why most of his new clients are referred by existing clients.

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“The remote filing service has been extremely convenient and timely for me. I usually fax all the documents to Joseph, and he emails me the completed PDF of my tax returns. I review them, and later authorize for e filing. In the end, he sends me a hard copy of all my tax documents for my records. I have been doing it for past three years, and it has been a very smooth process.”

— Bela G, IT Consultant, IL


“I have been using Keystone Tax Services for filing taxes for many years. As I was moving from state to state, they handled all my multi state returns very efficiently. Last year I moved back to India was able to prepare my return through KTS and got the best advise to meet my situation.”

— P. Kumar, Bangalore