William Perez

I believe in the power you have to take control of your taxes. And so I am willing to help anyone who asks for help with their taxes.

Feel free to contact me. I am always interested in hearing from readers like you. 

How to Contact William Perez

  • Phone: (415) 938-6478.
  • Email me (plain text email preferred).
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William Perez got his start in the tax world by working at the IRS as a graduate student intern. After going through an intense crash course of on-the-job training in individual and business tax, William was a public speaker delivering free workshops to the small business community. During the tax season, William prepared tax returns for individuals who came into the local walk-in center seeking free services. That was the first time he ever helped prepare a tax return for someone else. Working one-on-one with people on their tax returns opened William's eyes to a whole new experience: that helping people with their taxes provided a sense of genuine service. And that's when the thought occurred to William: he was sitting on the wrong side of the table. He needed to be working with clients to help them sort out their taxes.

After leaving the IRS, he worked at a few tax firms, and then started his own practice after a friend encouraged him to go out on his own. 

Over the years, William has developed hands-on expertise with personal and business tax. He enjoys helping people who have late returns, preparing US tax returns for people and businesses with foreign income, representing clients who are under audit, and representing clients who owe tax and need to deal with the IRS's collections department. 


Early in his career, William completed 640 hours of technical training in taxation as part of his on-the-job-training at the IRS. After leaving the IRS, William embarked on a program of self-study, which eventually lead to William successfully passing the enrolled agent exam. He enjoys doing his own tax research, and takes continuing professional education courses to stay up to date on the latest thinking in the tax world.

Before William became a tax professional, he completed a master's degree in philosophy at San Francisco State University.

William Perez

For me, tax is more than crunching the numbers. We need to move beyond just getting a tax return done, we need to put our country's tax rules to good use. "Knowledge is endless," British psychologist Maurice Nicoll once observed, "unless it leads to its own goal, which is its goodness. Good is the culmination of Truth."

That's why I take a holistic approach to tax. My goal is to understand a person's financial situation, figure out different ways we can apply the tax code to the situation, and discover cost-effective ways of achieving a desired financial outcome. To accomplish this work, I employ the skills of active listening, taking careful notes, and critical thinking. Always, we trying to make sure tax returns are prepared diligently, tax payments are sustainable for the client's situation, and that we are being proactive in protecting the client's right to pay the correct amount of tax.