Hello, I am Katerina Donckels – a California-licensed CPA with over 18 years of experience in U.S. and international tax, accounting, and tax audit. I founded this firm to offer clients something better than a typical firm experience: client-first service, deep technical knowledge, and a personal approach rooted in trust and long-term relationships that put clients first.
At my firm, you won’t be shuffled between departments or ignored, your tax return will not be outsourced to other countries .
You’ll work directly with me – and you’ll also benefit from the care and support of a small, experienced, and trusted in-office team I’ve built over the years. Most of my team came with me from earlier roles and share the same commitment to detail, respect to clients and their time, and doing things right.
I began my tax career at the Legal Department Outsourcing & Tax Compliance Division at Deloitte & Touche in Moscow, working with clients such as Campbell Soup, Bridgestone Tire, and Merrill Lynch. I earned my degree in Accounting and Economics from Moscow State University of Economics, graduating with honors.
After relocating to Los Angeles in 2008, I began giving back by volunteering with the IRS VITA (Volunteer Income Tax Assistance) program, helping low-income families file accurate returns. I then joined H&R Block, where I worked for 6 years, gaining extensive hands-on experience with individual and small business tax preparation.
During that time in 2011, I joined a CPA firm, newly established by Mark Cummins, CPA, as his first employee, initially to help with filing extensions. The firm had just a handful of clients. What started as a temporary role turned into a 15-year journey, during which I helped grow the practice into a thriving firm serving over 700 clients and became a full-time partner of the firm.
I led clients engagements, managed complex tax preparation, accounting, bookkeeping, QuickBooks setup, audit support, and advisory work for individuals and businesses across a wide range of industries. I was instrumental in the firm’s growth and direction over the next 15 years.
During that time, I earned my Certified Tax Preparer credential, became a Certified QuickBooks ProAdvisor, passed all three IRS Enrolled Agent exams, and completed my CPA licensure after the birth of my two daughters. To do something like this, one has to be extremely well organized, and this quality of mine is something my clients often commend.
At the same time, I also personally navigated and successfully managed my father’s immigration case – an experience that reinforced my belief in preparation, persistence, and standing up for what’s right. Those values are at the heart of how I serve my clients every day.
In 2025, as the founder of the firm expressed interest in stepping back from day-to-day tax work, it created a natural opportunity for me to establish my own independent practice. As part of that transition, I continue working with some of the firm’s long-standing clients, most of whom I had personally served for many years. I handled their tax preparation, accounting software, and ongoing support, and I’m proud to continue those relationships under my own firm today. It was the right moment for me to build something of my own – and so, Katerina Donckels CPA Inc. was born.
