Grant Cardone buys a lot of things: Cars, real estate, businesses. But there’s one test every purchase has to pass first, and it has nothing to do with whether he wants the thing or can afford it.

If he can’t write it off, he doesn’t buy it.

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“If I can’t write it off, I don’t buy it,” the real estate investor, author of “The 10X Rule” and CEO of Cardone Capital, said in a (1)TikTok video (1). “I will not spend any money that cannot be written off.”

And Cardone wants regular households to follow his lead. “If you want to make a simple rule for your household — if we can’t write it off, we’re not buying it. If the federal government doesn’t allow me a tax reduction, we are not going to do this,” he said. “When I buy a car, I don’t buy the car I want. I buy the car that I can write off.”

It sounds extreme. It is extreme. But the thinking behind it explains how wealthy people treat money differently — and there’s a version of it that works for a normal family budget.

A tax write-off (or deduction) is an expense the government lets you subtract from your income before calculating what you owe. Spend $10,000 on something deductible, and your taxable income drops by $10,000. Spend the same money on something non-deductible, and you pay tax on every dollar first, then spend what’s left.

That’s the logic behind Cardone’s rule. “Purchases that are not deductible cost me twice as much as those I can write off and save me 40% on my taxes,” (2)he has said (2).

The 40% reflects his tax bracket (most households would save less), but the basic direction still holds. A deductible dollar is always cheaper than a non-deductible one.

The car example shows how he applies it. Business vehicles can qualify for significant tax deductions, including depreciation. A personal luxury car, on the other hand, qualifies for far less, sometimes nothing. So Cardone buys the vehicle that the tax code rewards, not the one his taste prefers.

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The write-off rule isn’t the only trick Cardone uses. He has a whole set of spending habits that all point in the same direction: Keep your money working and stop it from slipping away (2).

His most famous rule is about where the money to spend actually comes from. “If I can’t pay for it out of passive income, I don’t buy it,” he says. “I don’t spend any of my earned income on myself. I use all of it to reinvest in my company, my brand, or to buy more real estate that produces income.”

He made this even clearer in a CNBC piece (3): “If I earned $100,000 a year from my job and $20,000 a year in passive income, I would try to only spend $20,000 on things beyond my basic living expenses.”

Before any purchase, he also rates the item on a 1–5 scale. 1 is “absolutely have to have it,” and five is “absolutely not necessary.” “4s and 5s are never bought and 3s are discussed,” he said (2).

Stack the rules together and a purchase has to clear three gates: Is it deductible? Can passive income pay for it? Do I actually need it? Most purchases fail at least one of the above.

There is a problem with taking the write-off rule literally: most of what a family buys just can’t be deducted. Groceries aren’t deductible. Same goes for rent, or shoes for school, for instance. When Cardone shared this rule before, one X user responded: “Groceries aren’t tax deductible. I guess I shouldn’t eat (4).”

Fair point. Cardone runs businesses, so a big chunk of his spending can legitimately go through them as deductible expenses. A salaried household doesn’t have that option. He’s also admitted his rules “require a great amount of discipline” and “might not be for everyone.” There were stretches when Cardone himself wondered why he was working so hard without enjoying the fruits of it (3).

The version of this rule that actually works for most families isn’t “never buy anything non-deductible.” Rather, before you spend, simply check whether the tax code can help you.

The IRS allows several deductions that ordinary households can claim, whether they itemize or not: like contributions to a traditional IRA (depending on income and workplace coverage), student loan interest, and the business use of your car or home if you have side income (5). The government effectively discounts every dollar you put through these channels.

So the family version of Cardone’s rule is simple: Max out the deductible moves first (like the IRA) before spending on things the tax code ignores. This way, you take the deductible opportunities before spending on the non-deductibles. Worth remembering the limit of this logic, though. A write-off reduces the cost of a purchase you’d make regardless. It never justifies buying something you don’t need.

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TikTok (1); AOL (2); CNBC (3); X (4); Internal Revenue Service (5)

This article originally appeared on Moneywise.com under the title: Grant Cardone has 1 rule for families on their way to wealth. Once you hear it, you'll rethink every purchase you make

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