Executive Summary
Grantor Retained Annuity Trusts (GRATs) and Intentionally Defective Grantor Trusts (IDGTs) are two estate planning strategies used to transfer appreciating assets to trusts while minimizing gift and estate taxes. Although both strategies can reduce transfer taxes, they differ significantly in how they are treated for estate tax purposes. Understanding these differences can help individuals and families determine which approach best supports their long-term wealth transfer goals.
Key Takeaways
- GRATs and IDGTs offer a strategic way to transfer future asset appreciation while effectively minimizing potential current or future gift or estate taxes.
- The treatment of estate tax varies considerably between these two trust types, particularly in cases where the grantor passes away during the planning phase.
- IDGTs are frequently chosen for long-term estate planning due to their enhanced flexibility and advantageous estate tax benefits.
Choosing between a GRAT and an IDGT depends on your estate planning objectives, the nature of your assets, and your long-term wealth transfer goals. Both strategies are designed to transfer future appreciation outside your taxable estate while minimizing gift taxes. However, they differ in how they are structured, how they are treated for estate tax purposes, and the planning opportunities they provide. Understanding these differences can help individuals, families, and business owners determine which strategy best aligns with their overall estate plan.
What Is a Grantor Retained Annuity Trust (GRAT)?
With a GRAT, the gift giver transfers assets to an irrevocable trust and retains the right to receive fixed annuity payments from the trust for a specified term, often from two to ten years. If the annuity lasts long enough and its payments are large enough, the annuity value retained by the grantor can be generally equal to the value transferred to the trust for actuarial purposes. With such an optimized annuity, the transferor is deemed to have made a taxable gift of such minuscule value that practically no gift tax is owed. But if the trust assets have a sufficiently large return over the life of the annuity, then the GRAT will come away holding real value at the end of the annuity term, having been successfully funded with minimal gift tax.
See How a GRAT Works in Practice
Want a more detailed look at how a GRAT may transfer appreciation to beneficiaries? Download our guide, Understanding a GRAT with a Practical Example, for a step-by-step illustration of a hypothetical two-year GRAT, from initial funding through the final distribution.
What Is an Intentionally Defective Grantor Trust (IDGT)?
A sale to an IDGT follows a similar path. Instead of retaining an annuity, the grantor sells appreciating assets to a specially designed trust and receives a promissory note in exchange. Over time, the IDGT repays principal and interest to the transferor according to the terms of the note. As with the GRAT, if the trust assets have a sufficiently large return over the life of the promissory note, then the IDGT will come away holding real value at the end of the note’s term, having been funded with minimal gift tax.
Why Grantor Trust Status Matters
One of the key advantages of an IDGT is that it is intentionally structured as a grantor trust for income tax purposes. As a result, the grantor — not the trust — is responsible for paying the income taxes generated by the trust’s assets.
Although paying the trust’s income taxes may seem counterintuitive, it can provide an important estate planning benefit. Because the trust’s assets are not reduced by annual income tax payments, they can continue to grow for the benefit of future beneficiaries. At the same time, the grantor’s payment of those taxes generally is not treated as an additional taxable gift, allowing additional wealth to be transferred without using more of the grantor’s lifetime unified gift and estate tax exemption.
An IDGT also offers another important advantage. Since the trust is classified as a grantor trust for income tax purposes, the sale of assets to the trust is typically overlooked for income tax considerations. This indicates that the sale generally does not activate capital gains tax, allowing appreciating assets to transfer into the trust without a realization event resulting in an immediate income tax expense.
These income tax advantages, combined with the estate tax benefits discussed below, are among the reasons IDGTs have become a preferred wealth transfer strategy for many high-net-worth individuals and families.
GRAT vs. IDGT: Similar Strategies with Different Estate Tax Results
In economic terms, GRATs and IDGTs are remarkably similar. In both cases, appreciating assets are transferred out of the grantor’s estate while a valuable payment right remains. Because the retained interest can be structured to approximate the value of the assets transferred, both strategies can result in little or no taxable gift. Despite these similarities, the estate tax treats the two structures very differently.
Comparison Table: GRAT vs. IDGT: Similar Strategies with Different Estate Tax Results
Feature | GRAT | IDGT |
Funding method | Retained annuity | Sale for promissory note |
Gift tax | Minimal taxable gift | Minimal taxable gift |
Estate tax treatment | Greater inclusion risk if grantor dies during term | Generally only remaining note value included |
Best planning horizon | Short-term | Long-term |
Flexibility | Moderate | Greater |
Understanding the Federal Transfer Tax System
The United States federal transfer tax system is comprised of two core taxes, two sides of the same coin: the gift tax and the estate tax. A third tax, the generation-skipping transfer tax, applies to certain gifts benefitting generations beyond one’s children. The gift tax is levied on gratuitous transfers made during life. The tax is based on the size of the gift — the bigger the gift, the bigger the tax —with a graduated tax rate that quickly reaches 40%. The estate tax is levied on all assets owned or controlled at death that will be gratuitously transferred following the owner’s passing. The tax is based on the size of the estate — the bigger the estate, the bigger the tax — with a graduated rate that quickly reaches 40%.
These taxes also have substantial exemptions and deductions. Indeed, the lifetime exemption from both taxes — set at $15 million per person in 2026 — is so large that most Americans will likely never have to pay either tax. The gift and estate taxes operate under a unified system, meaning that, as of 2026, a taxpayer can give away up to $15 million total, whether during life, at death, or partially both without incurring gift or estate tax. Other tax breaks such as the annual exclusion, medical exclusion, tuition exclusion, spousal deduction, and charitable deduction further erode the transfer tax base and benefit would-be transfer taxpayers. But for wealthy families and individuals, the exemptions and deductions may eventually run out, and mitigating the transfer taxes will be a matter of good wealth planning and execution. There are several prominent transfer tax strategies for transfer tax mitigation.
How GRATs and IDGTs Reduce Gift Taxes
When people think of a lifetime gift, they generally think of transferring an entire asset to a loved one with no strings attached. But gift givers are allowed to retain economic interest in the assets they transfer. The value of the interest the transferor retains will effectively shrink the value of the assets the transferor gives away, thus resulting in a smaller gift tax. In some circumstances, a transferor may retain an interest in transferred assets that is actuarially equal to the value of the transferred assets, resulting in a gift with no value and thus no gift tax. It is in these strange and somewhat befuddling circumstances that wealth planners can implement strategies to substantially reduce the gift tax.
Two of the best-known strategies for gift discounting with a retained interest are the Grantor Retained Annuity Trust (GRAT) and the sale to an Intentionally Defective Grantor Trust (IDGT).
Why the Estate Tax Treats GRATs and IDGTs Differently
A persistent failure of the federal tax code is its internal inconsistency. Such inconsistency is on full display with the GRAT and IDGT structures. While in real terms the structures are nearly identical, and the gift tax generally treats them as such, the estate tax views these structures very differently. That is, in each structure the transferor retains a value that remains in his or her taxable estate, an annuity or a promissory note and the estate tax applies to these modestly different structures in wildly different ways.
If the transferor dies during the GRAT’s annuity term, the estate tax generally includes the trust assets necessary to satisfy the retained annuity interest as though the annuity were going to be paid from the assumed income of the trust assets. This is a gross over-inclusion of the estate tax’s base. In simple terms, the full value of the GRAT’s assets will commonly be included in the transferor’s taxable estate if he or she dies during the annuity term. In economic and accounting terms, such tax inclusion overstates the value of what the grantor actually retained.
On the other hand, if the transferor dies while an IDGT’s promissory note remains outstanding, the taxable estate generally includes the note’s remaining face value with any accrued but unpaid interest. But the estate tax also allows the promissory note to be valued under traditional fair market principles including potential discounts for a low interest rate and lack of collateral. If the promissory note is well-drafted to achieve such discounts, the discounted note will be under-included in the estate tax’s base.
Estate Planning Implications for High-Net-Worth Families
The differing treatment of the GRAT and sale to an IDGT structure by the estate tax can create a pitfall for unwary planners. At the gift tax stage, the GRAT and the IDGT are close cousins. Both move appreciating assets outside the taxable estate while bringing an asset of comparable value back in. Both can dramatically reduce or even eliminate the taxable gift associated with the transaction. When the estate tax enters the conversation, however, those close cousins begin to look much less alike.
One retained interest may pull a substantial portion of the transferred assets back into the taxable estate. The other generally brings back only the retained promissory note — and perhaps even a note whose fair market value is far less than its outstanding principal balance. For high-net-worth families whose planning horizon extends many years into the future, such distinction lurking beneath the surface of these structures can lead to unintended tax consequences.
Why IDGTs Are Often Preferred for Long-Term Estate Planning
The GRATs have gotten the short end of this estate tax stick. Once used as a prominent transfer tax reduction strategy, the estate tax pitfalls built into the GRAT structure have gradually caused them to lose their effectiveness. In contemporary estate planning, GRATs are often kept to limited use with very short terms, most commonly two years, in hopes that the transferor will not shuffle off the mortal coil while still holding an annuity interest. Sophisticated estate planners generally embrace the IDGT as the structure to replace the GRAT, especially in longer term planning. The flexibility and potential valuation discounts with the promissory note, especially when compared to the annuity interest, have allowed the IDGT to largely eclipse the GRAT as the centerpiece to today’s estate tax planning.
Ready to Build Your Estate Planning Strategy?
Choosing between a Grantor Retained Annuity Trust (GRAT) and an Intentionally Defective Grantor Trust (IDGT) requires careful planning and a thorough understanding of the gift and estate tax implications. As part of LBMC’s Individual & Private Client Tax Services, our estate planning professionals help individuals, families, and business owners evaluate wealth transfer strategies that align with their long-term financial goals.
Because estate planning often involves legal, tax, and financial issues, LBMC works with clients and their lawyers to look into the tax effects of wealth transfer strategies and help clients make smart planning decisions.
Contact LBMC to discuss whether a GRAT, an IDGT, or another estate planning strategy may be appropriate for your long-term wealth transfer goals.
Content provided by Barrett Thomas, Estate and Gift Tax Consultant at LBMC.
FAQs
Is a GRAT or an IDGT better for my situation?
The right strategy depends on several factors, including the type of assets you own, your overall estate planning objectives, your expected investment returns, your health, and your long-term wealth transfer goals. While IDGTs are often preferred for longer-term planning, a GRAT may still be appropriate in certain situations. An experienced estate planning advisor can help evaluate which strategy best aligns with your circumstances.
When should I consider a GRAT or an IDGT?
These strategies are often a good fit for individuals and families who own assets that are expected to appreciate in value and may be subject to estate tax in the future. Business interests, closely held companies, real estate, and concentrated investment portfolios are common candidates. If business interests are involved, a current business valuation is often an important step in the planning process. In many cases, the earlier estate planning begins, the more planning opportunities may be available.
What happens if estate tax laws change?
Estate tax laws, exemption amounts, and interest rates change over time. Exemption amounts, interest rates, and other rules may affect how well a planning strategy works over time. Reviewing your estate plan regularly can help ensure it continues to reflect current tax law and your personal and financial circumstances.
How often should my estate plan be reviewed?
Estate plans should be reviewed whenever there is a significant change in your life, finances, or the tax law. Events such as the sale of a business, a substantial increase in wealth, changes in family circumstances, or updates to federal tax law may all be good reasons to revisit your plan.
Why work with LBMC on estate planning?
Estate planning often involves more than preparing trust documents. Tax, accounting, business, investment, and financial considerations all play a role. LBMC’s tax professionals work with clients, their legal counsel, and LBMC Wealth Advisors to evaluate the tax implications of wealth transfer strategies and help coordinate the planning process.
Can a GRAT and an IDGT be used together?
Yes. In many situations, a GRAT and an IDGT can be used as part of the same estate plan. Depending on your goals and the types of assets you own, these strategies — and others, such as a Charitable Remainder Trust (CRT) — may complement one another rather than serve as alternatives.
LBMC tax tips are provided as an informational and educational service for clients and friends of the firm. The communication is high-level and should not be considered as legal or tax advice to take any specific action. Individuals should consult with their personal tax or legal advisors before making any tax or legal-related decisions. In addition, the information and data presented are based on sources believed to be reliable, but we do not guarantee their accuracy or completeness. The information is current as of the date indicated and is subject to change without notice.
