About | R.C. Thornton Accounting Group LLC

R.C. Thornton Accounting GroupNot your typical Accounting Firm

Just as Arizona’s beautiful landscape is more than a desert, R.C. Thornton Accounting Group is more than a CPA firm.

What’s made us successful and our clients happy for the last forty years we’ve been in business is our ceaseless focus on rewarding our clients’ entrepreneurial spirit through accounting and planning that helps their businesses grow.

One key factor separates us from the rest:

We don’t just complete tax returns; we provide solutions. We advise you on how to navigate the financial direction of your company and your life, leaving no stone unturned.

Even our website exudes the R.C. Thornton Accounting Group difference by showing our commitment to technique, education, and effective communication. If you’ve had an “aha!” moment from just reading our website, imagine what we’ll be able to do for you as a client!

Wishing you and your business the best!

Our mission is to help clients achieve financial success.

Our Values

Accepting responsibility to get results

Our actions and results reflect our commitment to outstanding professional and personal quality. Our efforts demonstrate our desire to have enthusiastic client relationships.

Teamwork delivers better results

Leadership guides the members by obtaining the willing cooperation of the members. Teamwork comes from joint efforts while maintaining each member’s feeling of self-worth.

Changes are opportunities

There is a clear understanding of our direction even in a changing environment. We continually search for better ways to meet the needs and expectations of our clients.

Everyone should be a winner

Clients should receive value from the services we provide. The firm and members should receive compensation for their capital, risk, and efforts. The association between the clients, members and the firm should be enjoyable.

Our Team

Edward Dondlinger

Bio coming soon!

Greg Dutton

MTax Tax Partner

Greg joined the firm in 2004 and has over 25 years’ experience working in public accounting. He is dedicated to helping clients navigate complex tax matters and he enjoys working closely with clients to address intricate tax situations while developing strategies that support their long-term goals.

Greg earned his Master of Taxation degree from Arizona State University and he consistently participates in continuing professional education to remain current with the rapidly evolving tax environment.

Outside the office, Greg enjoys family life with his spouse, two children, and their lively household of two dogs and two cats. During breaks between busy seasons, Greg and his wife like to travel, both with and without the kids.

Zach Mashni

CPA Accounting Manager

Zack joined the firm in 2025 and has worked in public accounting for 4 years. He started his career doing audits for Deloitte and Touche in Dallas, Texas. He is dedicated to assisting clients with audit, reviews, and compilations to ensure accurate and complete financial reporting.

Zack earned his master’s in accounting from Southern Methodist University. He obtained his Certification in Public Accounting in 2024 after meeting all exam and experience requirements. He is currently certified by the Arizona State Board of Accountancy.

Outside of work, Zack enjoys golfing and traveling with his friends and family.

Joseph Jackson

Senior Tax Associate

Joining the firm in 2025, Joe brings more than 20 years of public accounting experience with a primary focus on tax services for individuals, businesses, and organizations. Throughout his career, he has helped clients navigate complex tax laws, maintain compliance, and identify tax-saving opportunities through thoughtful planning and personalized guidance. Joe is committed to providing responsive, accurate, and practical tax solutions that help clients make informed financial decisions with confidence.

Joe earned a Master of Business Administration (MBA) from the University of Phoenix and believes that continuous professional development is essential in today's ever-changing tax environment. By staying current with evolving tax legislation, regulations, and industry best practices, he strives to provide proactive advice and exceptional service that meets each client's unique needs.

Outside of the office, Joe enjoys quality time with family and spending time on the golf course whenever he has the opportunity. He values the balance these activities bring and the perspective they provide both personally and professionally.

Kitt Compton

Operations Manager

Kitt serves as Operations Manager for R.C. Thornton Accounting Group, guiding the administrative, operational, and organizational functions that drive the firm’s success. Since she joined the firm in 2016, she oversees staff coordination, technology systems, and client service standards, ensuring the office operates at peak efficiency. Kitt's commitment to exceptional service makes her a trusted resource within the firm.

Kitt loves spending time with family, friends, and cats. As an Arizona native, she enjoys the beautiful desert views and sunsets.