For families with significant assets in Southern California, 2026 is a planning milestone because several federal transfer tax numbers reset and update at the start of the year. Even when federal exemptions are high, the best opportunities often come from using time, appreciation, and clear documentation, not from rushing at the end. An intentionally defective grantor trust California strategy is one tool that can be considered as part of a broader plan to transfer future growth outside a taxable estate while keeping the income tax burden with the grantor.

An IDGT is a trust designed so that, for income tax purposes, the grantor is treated as the owner, but for estate tax purposes the trust assets are generally outside the grantor's taxable estate if structured and administered properly. In plain terms, the trust is “defective” only in the income tax sense, which is intentional. This arrangement can allow the trust assets to grow for beneficiaries while the grantor pays the ongoing income tax, which may further reduce the grantor's taxable estate over time.

Many IDGT plans use either a gift to the trust, a sale to the trust, or a combination of both. A common structure is a sale to an IDGT using a promissory note, where appreciating assets are sold to the trust in exchange for a note that provides cash flow back to the grantor. The goal is that asset growth in the trust exceeds the note's interest cost, leaving the “excess” appreciation to beneficiaries. Because this is technical, grantor trust planning is usually paired with careful drafting, consistent administration, and coordination with tax professionals.

Valuation and substantiation matter more than the label on the strategy. Transferring closely held business interests, real estate, or partnership interests may require a qualified appraisal and clean records to support the value used for the transaction, especially where valuation discount appraisal concepts might apply. Separately, taxpayers often ask whether they must file Form 709 gift tax return paperwork, which depends on how the transfer is structured and whether annual exclusions or lifetime exemption are being used. The compliance steps are part of making the plan durable, since the IRS typically expects the reporting to match the legal structure.

When clients talk about acting “before 2026,” the question is usually about federal thresholds and legislative uncertainty, not a single California deadline. The IRS currently lists the federal basic exclusion amount as $15,000,000 for 2026 (up from $13,990,000 for 2025), and those numbers can affect how much can be transferred without federal estate or gift tax. For reference, see: https://www.irs.gov/businesses/small-businesses-self-employed/whats-new-estate-and-gift-tax. This article is general information, not legal advice.

IDGTs are not a fit for every estate, even at higher wealth levels. They work best when there are assets likely to appreciate, a clear reason for the transfer, and a realistic plan for cash flow, taxes, and administration. They also work best when the plan is integrated with the rest of the estate plan, including liquidity planning and successor decision-makers, so that the trust can be managed consistently if health or family circumstances change. A helpful overview of gift and estate tax concepts is available at https://www.irs.gov/newsroom/estate-and-gift-tax-faqs, and general background on grantor trusts can be found at https://www.law.cornell.edu.

Key takeaways

• An intentionally defective grantor trust California plan may transfer future appreciation while the grantor pays the trust's income tax.
• Sales to an IDGT using a promissory note can be effective but require careful valuation, documentation, and consistent administration.
• Planning ahead of 2026 is often about coordinating exemptions, reporting, and long-term management rather than racing a single deadline.

If you want to evaluate whether an IDGT fits your estate plan and how it may interact with 2026 transfer tax numbers, a structured review of assets, cash flow, and existing documents can clarify options and next steps. Call Westlake Law Group at (818) 444-2022. 30699 Russell Ranch Road, North Building, Suite 210, Westlake Village, California. Virtual consultations are available throughout Southern California.