Katherine E. Ayer (CPA), of Arroyo Grande, has prepared tax returns for over 20 years and has been helping small businesses with their accounting and financial reporting for nearly as long. After many years of experience gained while working for local firms in Arroyo Grande, Katy established her own CPA practice in January of 2020.

Katy handles tax returns for individuals and small businesses, as well as estates and trusts. As a QuickBooks ProAdvisor, she is well qualified to help with your accounting setup and ongoing operations as well.

Katy received her undergraduate degree from Bryn Mawr College in Pennsylvania and holds a PhD in German Literature from Princeton University. She spent several years in higher education before pivoting toward the world of tax. After completing the required accounting and business course work, she obtained her CPA certification in 2013.

Katy’s background teaching German has served her well in the world of tax and accounting. As a former language teacher, she knows the importance of taking the time to make sure her clients understand key concepts.

When Katy is not preparing tax returns, she can be found knitting, practicing the piano, or exploring the backcountry with her husband and their dog.



Katy is an enthusiastic supporter of youth activities, particularly activities related to science and technology education. Katy is currently a Board Member of the Unitarian Universalists San Luis Obispo County, and is the Treasurer of the The Samuel Jeffers Childhood Cancer Foundation based in Grover Beach, California.


“My goal is to give you confidence that your tax issues are in good hands and to give you the accounting tools you need to help your business grow.”