Thill And Leonard CPAs

Providing tax and accounting services to Kansas City individuals and businesses

Our Services

Thill & Leonard, CPAs, LLC is a company built around quality service and a strong commitment to its clients and our community. We are proud to offer our customers the following services:

Services For Individuals


In addition to tax planning, Thill & Leonard, CPAs prepares federal, state, and local income tax returns as well as estate and trust returns. We can also provide assistance or referrals for other personal financial and tax issues.

Some of the services we provide:
  • Income Tax Prep:
    • Federal, State & Local Returns
    • Estate and Trust Returns 
  • Personal Assistance and Referrals for Most types of Financial and Tax Issues

Services For Businesses


In addition to providing business income tax preparation services for federal, state, and local returns, Thill & Leonard, CPAs also provides accounting support for your business. These services can range from occasional contacts from you with specific questions to quarterly, monthly, and annual write-up and accounting services. We can also assist you in running your accounting department.

Some of the services we provide:
  • Income Tax Prep:
    • Federal, State & Local Returns
    • Estate and Trust Returns 
  • Accounting Support
    • Answering Specific Questions
    • Quarterly, Monthly and Annual Write-Up
    • Accounting Services
    • Oversee Your Accounting Department

Meet Our Team

About Thill & Leonard CPAs

Thill & Leonard, CPAs, LLC is a company built around quality service and a strong commitment to its clients and our community. We work with you to ensure an experience that will satisfy us both. The staff at Thill & Leonard, CPAs understands the importance of reliable service and long-term, mutually beneficial relationships with clients. This firm was built on its professional reputation and referrals from its past and current clients and it continues to grow because of our positive interactions with clients and our active presence within the community. Thill & Leonard, CPAs, LLC has been in business since 1989. We specialize in tax, consulting, and accounting services, provided to small businesses and individuals. Our client base is varied with experience in the video/film production industry including related small marketing/advertising agencies and website development companies. We also are experienced with the renovation, restoration, & remodeling industry, the financial planners & advisers related industries, the not-for-profit industry, the real estate industry, dental & medical practices, and other service based industries.

Picture of Mark Thill

Mark Thill

Mark started his career in 1984 after receiving a Bachelor of Science, Business Administration in 1983 and a Bachelor of Science, Accounting in 1984 from the University of Kansas. Over the next few years, Mark gained experience working for the international firm of Coopers and Lybrand, CPAs in their Tulsa, Oklahoma and Kansas City, Missouri offices as well as the national firm of Baird, Kurtz, and Dobson CPAs providing auditing, tax, and other special services for private and publicly held clients in a wide variety of industries. In 1989, he started Mark William Thill, CPA, as a sole proprietorship. In 2006, he merged with Debbie Leonard, CPA to form Thill & Leonard, CPAs, LLC.

Picture of Sheila Thill

Sheila Thill

Sheila Thill graduated from the University of Kansas with a personnel degree. She started working part-time for Mark William Thill, CPA in the summer of 1997 as an accounting and administrative assistant. In 2005, she was promoted to the full-time position of Office Manager for Thill and Leonard CPAs, LLC. Her duties include client relations, inter-office communication, and scheduling.

Picture of Steven Thill

Steven Thill

Steven graduated from the University of Kansas with a Bachelor of Science in Accounting, and a Concentration in Entrepreneurship in 2010. Upon graduation, Steven went on to work for the IRS as a 1040X Tax Technician, allowing him to gain valuable knowledge into the world of tax from the IRS standpoint. Looking to expand his skillset and delve further into day-to-day accounting functions, Steven was hired on as a Staff Accountant for BillSoft, Inc., assisting the CFO in managing the company’s financials. He then went on to join BillSoft Inc.’s sister company, BillSoft Services, Inc., as a Tax Compliance Analyst, focusing on sale, use, and telecommunications tax preparation for several Fortune 500 clients. Bringing with him a wealth of insight from multiple perspectives and experience in personal and corporate tax and accounting, Steven joined Thill and Leonard CPA in the Fall of 2014.

Picture of Debbie Leonard

Debbie Leonard

Debbie met Mark way back while in the accounting program at KU- and they have been colleagues and friends ever since. Graduating with honors in 1983, with a double major of Accounting and Business Administration, Debbie went to work with the international firm of Deloitte, Haskins & Sells (now Deloitte & Touche). Working in Kansas City and the San Jose, California offices in the audit and tax departments during the rise of Silicon Valley provided unique experience and access to start up companies and the venture capital arena. Debbie also worked with the firm of Coopers & Lybrand in the consulting and tax department. Debbie earned her MBA in Finance and Marketing in 1994. Gaining experience in audit, tax, consulting and her true passion, marketing, allows Debbie to provide exemplary business advice and guidance encompassing all dimensions of a business. Other positions she has held in private business, include Tax Specialist at Commerce Bancshares, and Director of Finance for Tivol Plaza, Inc.. In 1994, Debbie decided to take her part time practice full time and never looked back. In 1994, Debbie was awarded the SBA “Small Business Advocate of the Year” for the State of KS, and the Midwest Region. A much sought after speaker on marketing, networking and tax issues, Debbie also was an adjunct professor at Devry University teaching finance, and developer and instructor of the Quickbooks class at Johnson County Community College. In 2006, Debbie merged with Mark Thill and remained a partner working part time in Business Development. During this time, Debbie was CFO of Jones Development Company, LLC, a build-to-suit real estate developer. Debbie has extensive experience in real estate and earned her CCIM (Certified Commercial Investment Manager) in 2010. Debbie was nominated for the Business Journal’s, CFO of the Year in 2011. Debbie is a licensed CPA in Kansas and Missouri. In the fall of 2012, Debbie rejoined Thill & Leonard on a full time basis and is thrilled to be back working with her clients! Debbie is very active in the community, serving on the local board of the Women’s Commercial Real estate group, KC CREW, the board of the Olathe Lacrosse Club, and participating in numerous charitable and networking organizations. Debbie enjoys biking all over the midwest with her significant other, Jay, and working on a novel she is writing. Their combined family of four kids and three dogs, love the outdoors, skiing and attending KU sporting events.

Watch Debbie’s interview on MSNBC’s Your Business
Characters to Avoid at Networking Events.

Picture of Anna Crenwelge

Anna Crenwelge

Anna joined the staff of Thill & Leonard, CPAs as a full time staff accountant in November of 2009 after moving back to Kansas from Dallas, Texas. Anna graduated with honors from the University of Dallas in May, 2008, obtaining a bachelor’s degree in psychology. She graduated with honors from the Master’s of Accounting Program at the University of Missouri, Kansas City Henry Bloch School of Business in December 2014. Anna became a licensed CPA in July of 2017.

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