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Mona L. Casillas
Enrolled Agent

Phone 832-850-7087 ext. #107
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Mona Casillas received a B.B.A. in Accounting from the University of Houston-Downtown in 2005 and a B.B.A in Finance from the University of Houston-Downtown in 2007. Upon graduation in 2005, Mona joined the local firm of Maddox, Thomson and Associates as a tax accountant and progressed to a senior tax accountant preparing various types of tax returns for high net worth individuals and their related businesses and trusts. Mona earned her enrolled agent certification from the Internal Revenue Service in 2012; obtaining the highest credential the IRS awards. In 2013, Mona started working at Linn Thurber, LLP as a senior tax accountant and progressed to tax supervisor focusing more on trust work for high net worth individuals and families. In January 2017, Mona joined the team at Atkins & Grainger, PLLC bringing with her over 10 years of experience. 

Mona is also a United States Army veteran having served a tour overseas in Kitzingen, Germany from 1993 to 1996 and finishing up at Ft. Bliss, TX in 1997. She proudly served as a telecommunications multichannel transmission systems operator and received an honorable discharge. Mona has lived in several places in the U.S., but has called Houston, TX home since 2002. She lives with her husband and daughter in The Woodland Heights. Mona enjoys spending her personal time gardening, traveling, watching movies and doing family activities like comic, anime and cosplay conventions. She is also an avid baker.