29 Sep Pay the Tax Now, Keep the Growth Forever

An intentionally defective grantor trust, or IDGT, is an irrevocable trust designed to do two things at once: remove assets from your taxable estate while keeping you responsible for the trust’s income taxes. That combination may sound like a raw deal until you understand the economics.

The trust is irrevocable, so the assets are outside your estate. But it includes a specific power that makes the IRS treat you as the owner for income tax purposes. The trust’s income shows up on your personal return. The trust’s assets don’t show up in your estate.

That split is what makes it work.

Two Tax Systems, Two Different Answers

The federal tax code doesn’t speak with one voice. The income tax rules and the estate tax rules each decide independently whether you “own” something.

For income tax, the question is whether you’ve retained enough control or benefit that the trust’s income should be taxed to you. Certain powers trigger this result: the ability to substitute trust assets for assets of equal value, or lending trust assets without adequate security. These are the grantor trust triggers under sections 671 through 679 of the tax code. If the trust has one of these powers, all its income shows up on your personal return.

For estate tax, the question is different. It’s whether you’ve given up enough control that the trust’s assets are no longer part of your taxable estate. An irrevocable trust, properly drafted, answers yes. The assets are out.

An IDGT engineers both results at the same time. You pay the income tax (you’re the income tax owner), but the assets aren’t in your estate (they’re removed for estate tax). That’s the “defect.” And it’s intentional.

Why Paying the Tax Is the Point

Most people hear “you pay the income tax on trust assets you’ve already given away” and think that sounds like a bad deal. It’s the opposite.

Every dollar of income tax the grantor pays on trust income is a dollar that doesn’t come out of the trust. The trust grows without any tax drag. Meanwhile, the grantor’s own estate shrinks by the amount of tax paid. And the IRS doesn’t treat those tax payments as additional gifts to the trust. It’s a tax-free wealth transfer that looks like a tax obligation.

Say the trust earns $200,000 in a year. If the trust paid its own taxes, it might keep $150,000 after tax. But because the grantor pays the tax personally, the trust keeps the full $200,000, and the grantor’s estate is $50,000 smaller. Over 20 or 30 years, that income tax subsidy compounds into millions.

The Seed Gift

You can’t just sell assets to an IDGT on day one. The trust needs economic substance. In practice, the grantor makes an initial gift to the trust, typically 10% to 20% of the total value they plan to transfer. This is called the seed gift, and it uses the grantor’s lifetime gift and estate tax exemption.

With the exemption now at $15 million per person ($30 million for a married couple), there’s room to make substantial seed gifts without triggering gift tax.

The Installment Sale

After the seed gift, the grantor can sell additional assets to the IDGT in exchange for a promissory note bearing interest at the applicable federal rate (the AFR). Because the trust is a grantor trust, the sale isn’t a taxable event. The IRS treats it as a transaction between the grantor and themselves.

The real power is in the spread. If the transferred assets appreciate faster than the AFR on the note, the excess growth passes to the trust beneficiaries free of gift and estate tax. A $10 million asset growing at 8% annually, sold to the trust for a note at 4% AFR, transfers roughly $400,000 a year in appreciation to the next generation, with zero tax cost.

Who It’s For

IDGTs work best for families with appreciated or appreciating assets: operating businesses, real estate, investment portfolios, interests in private equity or venture funds. They work best when the grantor has enough income to absorb the trust’s tax burden without financial strain. And they work best when the goal is long-term, multigenerational wealth transfer, not short-term liquidity.

They’re also one of the best vehicles for locking in the current $15 million exemption. Gifts to an IDGT are completed transfers. Once the assets are in the trust, they’re out of the estate. For families thinking about pre-sale planning, an IDGT is often the centerpiece of the structure.

What It Doesn’t Do

An IDGT doesn’t protect you from income tax. You’re still paying it. And it doesn’t give you access to the trust’s assets after the transfer. Once they’re in, they’re in. If the grantor’s financial situation changes and they can’t afford the trust’s income taxes, the trust agreement should include a mechanism allowing the trustee to reimburse the grantor for taxes paid. But that provision should be used sparingly, not as a regular income stream.

An IDGT also doesn’t automatically solve the generation-skipping transfer tax. That requires a separate GST exemption allocation, which is covered in the next articles in this series.

Is an IDGT the right tool for your family?

For advisors: Have a client dealing with this? I do quick consult calls for advisors working through complex planning situations.

Schedule a call: https://lgarzalaw.com/schedule-online/

For business owners and families: At Garza Law, we are selective in choosing our clientele. We work with a select group of families every year to help them protect their legacy. If what you read here raised questions about your own situation, you can apply here:  Apply Here

Related Articles

Grantor Trust Income Tax Strategy. A deeper look at how grantor trust status works and why it matters.

Revocable vs. Irrevocable Trusts. The foundational distinction between the two trust categories.

Estate Planning Before Selling Your Business. Why the best time to plan is before the deal, not after.