The $40,000 Tax Mistake My Client’s CPA (almost) Made

UPDATED for 2026

I make it a part of my regular services to ensure that the CPAs my clients work with aren’t making any costly mistakes. And trust me, even the best of CPAs can make a mistake on a tax return.

It’s easy to see why…

In 2025, the IRS received around 165 MILLION tax returns. With that many returns to file and that short of a turn-around time, it’s no wonder there are mistakes on tax returns. Sometimes they’re costly ones that even your CPA might miss.

AND let’s be realistic on the business owner’s end of things. It’s still an INSANE proposition that we need to file taxes a mere 11 weeks after the year officially closes.

So it’s easy to see how CPAs are BUSY. Even a small firm is likely processing thousands of tax returns each season, which means things can easily be overlooked. And that can lead to mistakes on your tax return.

Now, I often check tax returns for my clients that have already been prepared by their CPA. But what happens if you don’t have a second pair of eyes scanning your return before you file it? Who checks the CPA’s work then? The answer is the IRS themselves.

And you really don’t want to be waiting for the IRS to tell you if your taxes were filed correctly or not!

In the last few years I have caught hundreds of thousands of dollars in mistakes made on business tax returns. One situation a few years back was particularly memorable because it included a mistake to the tune of $40,000.

How did I discover this oversight on the CPAs part? I saw that their CPA missed checking ONE box on the form before filing it. This ended up saving my client from paying an additional $40,000 in taxes.

Another year one of my client’s CPAs “forgot” that they had already paid estimated taxes (because the software didn’t carry over the payments). Because of this oversight, that client had to pay an extra 70K!

So CPAs DO make mistakes on tax returns. I see it all the time. Having someone take that “second look” at your taxes becomes a really big deal in moments like this.

Not only that, but having a second look at your taxes is also important when you hire a “DIY” option like Turbotax or H&R block, or if you don’t have the proper bookkeeping in place.

I had a client that didn’t have their books books properly prepared. So when their CPA filed their taxes, they missed a lot of transactions that weren’t recorded correctly.

Thankfully, my client and I were able to map those easily enough to take in the next year so they didn’t lose out on those deductions.

What is the bottom line when working with CPAs? Two things…

1-You need to have clean and accurate books if you want to file accurate taxes

Even if you’re not working with a CPA, ensuring that your bookkeeping is accurate is job one. Because technically, it is NOT your CPA’s job to ensure that your bookkeeping is correct. (Read about that right HERE).

2-It (literally) pays to get a second look at your taxes before you file, even if your taxes were prepared by a CPA.

No matter who prepares your taxes, whether you DIY them or work with a bookkeeper or a CPA, a second look can be a lifesaver.

If you are worried about the status of your books or you’re interested in that “second look,” book a call with me so we can chat.

My goal is to keep my clients as compliant as possible, and I’m here to help you do just that. So if you’re ready to chat, let’s plan it! Book your call HERE and let’s see how I can help you take charge of your taxes!

Until next time,

Love, light, and MONEY, honey…

Kaylee

P.S. Are you getting all the business tax deductions that you’re owed? Even when you’re working with accountants and bookkeepers, it’s not always easy to catch all the deductions you could be taking.

My handy tax deduction checklist can help!

Download “20 Common Tax Deductions Even Experienced Entrepreneurs Might Miss” right here, and get together with your CPA or bookkeeper to make sure your business is taking all possible deductions for your biz!