Most people use "aggressive tax strategy" as a single phrase, as if every plan that lowers your bill carries the same level of audit exposure. It doesn't.
Aggressive can mean two very different things. It can mean using every legitimate deduction, credit, and structure the code allows. Or it can mean stretching a position past where the IRS would defend it, hoping no one looks.
The first one is what good tax planning is supposed to do. The second one is what gets families pulled into multi-year examinations, back-tax bills, and sometimes a malpractice claim against the advisor who set the whole thing up.
Knowing the line between the two is most of the work.
I've written about a five-figure tax mistake I watched unfold on a cruise ship, and the lesson there applies here. The cost of a bad position never feels real until the bill arrives.
Three optimization plays that are clearly safe
There's a wide menu of strategies that meaningfully reduce taxes without putting you in the IRS's crosshairs. A few of the most common:
- Entity selection. Choosing the right operating entity (S-corp, C-corp, LLC) for your facts can move tens of thousands of dollars over a few years. The mechanics are well-documented and well-tested.
- Retirement plan structures. Cash balance plans, defined benefit plans, and properly designed 401(k)s for owners can shelter substantial income. The rules are detailed but the IRS does not consider them aggressive when the plan is administered properly.
- Charitable structures. Donor-advised funds, qualified charitable distributions, and well-run private foundations are all on solid ground.
These are the kinds of moves where the rules are clear, the documentation is straightforward, and your advisor can defend the position without flinching.
Three plays that look optimized but carry real risk
The strategies I push back on most are the ones that look like the safe ones above but cross a line on the details.
- Captive insurance abused for tax purposes. A genuine captive serving genuine business risk is fine. A captive that is mostly a tax vehicle has been on the IRS's "Dirty Dozen" list and gets unwound regularly.
- Conservation easements that are valuation-heavy. Real conservation transactions exist. Syndicated easements where the deduction multiple is unusually high are a recurring audit target.
- Trust arrangements that move income without moving control. If the IRS can show that the family still functionally controls the asset, the structure collapses.
The pattern across all three is the same. The structure is technically legal, but the substance doesn't match the form. That's the trigger for trouble.
How the IRS evaluates "economic substance"
Strip away the jargon and the test is simple.
The IRS asks whether the transaction had a real, non-tax business purpose, and whether it actually changed your economic position in a meaningful way. If the only effect of the transaction was to lower your tax bill, the doctrine lets the IRS unwind it.
This is why my rule of thumb has always been the same. Would I defend this position in front of an examiner without flinching? If the answer is yes, we're on solid ground. If the answer requires an explanation that depends on a footnote in a court case, we're probably too aggressive.
When to bring in a tax attorney
A good CPA covers most of the ground. There are a few situations where you want a tax attorney in the room:
- Any transaction with a documented IRS audit history.
- Cross-border structuring.
- Anything where the deduction relies on appraisal or valuation.
- Any structure that an outside promoter brought to you with a marketing deck.
The last one is the most important signal. If a strategy is being sold to you by someone whose business model is selling that strategy, get a second opinion before you sign.
The conservative read is usually the right one
I'm not in the business of leaving deductions on the table. I'm in the business of helping families build wealth they get to keep.
Aggressive within the rules, defensible to the dollar, and easy to explain in plain English. That's the standard.
If you want a review of your current positions through that lens, book a tax strategy review.