There’s something oddly satisfying about watching a trainwreck in slow motion—unless it’s your business, and the train is your tax bill. At Seed Financial, we review dozens of tax returns every month from business owners who came to us after their last accountant cost them thousands (sometimes millions) in missed opportunities, avoidable penalties, or just plain bad advice.

Here are a few of the most expensive, avoidable tax mistakes we see—every. single. month.

1. The "Oops, I Didn’t Elect S Corp Status" Mistake

The Cost: $14,000–$50,000+ per year in unnecessary self-employment tax.

A solo business owner making $250K in net income? Should have been an S Corp. Instead, they paid SE tax on every dollar. We’ve seen clients overpay for years because no one told them how or when to make the election.

👉 Seed Move: We not only help file the election—we build a full compensation plan that balances IRS compliance and tax savings.

2. The "My Bookkeeper Is a Spreadsheet" Disaster

The Cost: Inaccurate tax filings, missed deductions, and IRS notices that could have been avoided.

Bad books = bad tax returns. We’ve seen business owners with six-figure revenue relying on outdated spreadsheets or bookkeepers who don’t reconcile regularly. The result? Tax returns that don’t match reality.

👉 Seed Move: Our bookkeeping integrates with our tax strategy team, so every dollar is accounted for with strategy baked in.

3. The Real Estate Professional Status Miss

The Cost: $20K–$100K+ in unused passive losses.

Client owns 10 properties and qualifies for real estate professional status—but their CPA never filed the election. Years of passive losses sat idle while the client paid full freight on W-2 and business income.

👉 Seed Move: We proactively review qualifications and handle the elections so your deductions actually do something.

4. The C Corp That Shouldn’t Exist

The Cost: Up to 45% in double taxation on distributions.

A profitable service business structured as a C Corp? Yikes. After corporate tax, then personal tax on dividends, the owners lost nearly half of what they made. And for what? A structure that didn’t match their needs.

👉 Seed Move: We evaluate entity structure in the context of your goals—not just your current income.

5. The SEP IRA Black Hole

The Cost: Missed opportunities to contribute 2–3x more through better plans.

SEP IRAs are easy. But they’re rarely the most efficient. We’ve seen business owners with high cash flow and no employees who could have saved far more with Solo 401(k)s or defined benefit plans.

👉 Seed Move: We optimize your retirement contributions for the maximum deduction and long-term wealth.

6. The DIY Tax Filer With 3 LLCs

The Cost: Endless Schedule Cs, audit risk, and overpaid taxes.

Running multiple businesses and filing through TurboTax isn’t just brave—it’s financially reckless. We’ve seen business owners overpay by tens of thousands simply because they didn’t know better.

👉 Seed Move: We consolidate, restructure, and handle filings across all entities. No guesswork.

7. The Accountant Who Doesn’t Ask Questions

The Cost: All of the above.

If your accountant isn’t digging into your goals, your plans, or your future—you're not getting strategy, you're getting software with a face.

👉 Seed Move: Our entire firm is built around proactive planning. We don’t wait for tax season. We design your outcome.

Don’t Be the Next Horror Story

These aren’t rare edge cases. These are common mistakes that cost real money.

The good news? They’re fixable. And the earlier you fix them, the more you save.

Get a free risk review from Seed. We’ll tell you what your last accountant missed—and how much it’s costing you.

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