Trust Beneficiary Inherited IRA: See-Through Trusts, Conduit vs Accumulation, and the 10-Year Rule

Naming a trust as your IRA beneficiary complicates everything — the 10-year depletion rule, annual RMD requirements, and tax treatment all hinge on a specific set of trust-design requirements that most trusts weren't written with the post-SECURE Act world in mind.

Why naming a trust as IRA beneficiary creates complexity

An IRA passing directly to a named individual is relatively straightforward: the beneficiary files paperwork, establishes an inherited IRA, and takes distributions under the 10-year rule (or stretch, if they're an eligible designated beneficiary). The tax is predictable; the timeline is clear.

When a trust is named instead, two layers of law collide. IRA distribution rules operate at the federal level under IRC § 401(a)(9), requiring distributions be made based on a human being's life expectancy. A trust is not a person. Congress and the IRS created a workaround — the see-through trust rules — that let the IRS look past the trust entity to the human beneficiaries behind it. But this only works if the trust satisfies specific technical requirements.

Trusts are commonly named as IRA beneficiaries for legitimate reasons: protecting a spendthrift beneficiary, controlling access for a minor, coordinating with special needs planning, or ensuring assets go to the right branch of a blended family. These are real planning goals. The problem is that many such trusts were drafted before 2020 without accounting for SECURE Act changes, and even post-2020 trusts may have design flaws that prevent see-through qualification.

See-through trust requirements

For a trust to qualify as a see-through trust under the final regulations (Treas. Reg. § 1.401(a)(9)-4), it must meet three requirements:¹

1. Valid under state law. The trust must be a legally valid trust under the applicable state's law (or would be, but for the fact that there is no corpus at the time the IRA owner names it as beneficiary).
2. Irrevocable at death. The trust must be irrevocable, or must contain language making it irrevocable upon the death of the IRA owner. A revocable living trust typically satisfies this if its terms specify irrevocability on death — which is standard drafting. A trust that remains amendable after the IRA owner dies fails this requirement.
3. Beneficiaries identifiable from the trust document. The beneficiaries of the trust who have an interest in the IRA must be identifiable — meaning you can determine who they are by reading the trust document. Beneficiaries don't need to be named individuals at the time of death (a class such as "my then-living children" is sufficient), but the class must be determinable. A charitable remainder trust with an open class of potential future beneficiaries creates problems here.

Conduit trust vs. accumulation trust: the core distinction

A trust that qualifies as see-through falls into one of two categories, and which one determines both who the "designated beneficiary" is for RMD purposes and how distributions are taxed.

Conduit trust

A conduit trust requires that any distribution the trust receives from the IRA must be distributed immediately to the trust beneficiaries — the trust cannot retain or accumulate IRA proceeds inside the trust. Every dollar coming out of the inherited IRA flows directly to the named beneficiary in the same tax year.

Because distributions pass through automatically, the IRS "looks through" the trust to the human beneficiaries who actually receive the money. Those beneficiaries are treated as if they were the direct IRA beneficiaries for distribution period purposes:³

• If all conduit beneficiaries are non-EDB individuals: the 10-year depletion rule applies (same as if the individual had inherited directly)
• If the conduit beneficiary is an eligible designated beneficiary (e.g., a disabled individual): the stretch IRA can apply through the trust
• Annual RMDs during the 10-year window are taxed at the beneficiary's individual rate — not at compressed trust brackets (since distributions pass through)

Accumulation trust

An accumulation trust gives the trustee discretion to retain IRA distributions within the trust rather than passing them out immediately. This creates control (and creditor protection) but comes with serious tax consequences and a stricter see-through test.

Because distributions can be accumulated inside the trust, the IRS cannot simply "look through" to current distributees — it must consider all potential beneficiaries who could ever receive the money, including remainder beneficiaries. This means:³

• All current and remainder beneficiaries must be identifiable individuals (or qualifying see-through trusts themselves). If any beneficiary in the chain is a non-individual — a charity, an estate, another non-qualifying trust — the see-through fails entirely.
• If it does qualify, the applicable distribution period is based on the oldest trust beneficiary's age (the "oldest beneficiary" factor), even if that beneficiary has only a remote remainder interest.
• Distributions retained inside the trust are taxed at compressed trust income tax brackets — reaching the 37% federal rate at approximately $16,000 of taxable income in 2026, compared to $626,350 for a single individual filer.⁴

The tax cost of accumulating inside the trust: a concrete illustration

The trust bracket compression is the central planning problem for accumulation trusts. Most inheritors underestimate how punishing it is.

The practical implication: unless the accumulation trust is serving a compelling non-tax purpose (special needs planning, protecting a beneficiary with significant creditor risk, or controlling distributions to a minor), the tax drag of retaining distributions at trust rates almost always outweighs the control benefit. Most estate planning attorneys now recommend conduit trust structures for IRA assets, or direct inherited IRA designations where trust-level control is not essential.

Annual RMD requirements for trust beneficiaries under T.D. 10001

The 2024 final regulations added a critical rule that affects trust beneficiaries just as it affects individuals: when the IRA owner died after their required beginning date (RBD), annual RMDs are required during the 10-year depletion period — not just full depletion by year 10.⁵

The RBD is April 1 of the year following the year the IRA owner turns 73 (for those born 1951-1959) or 75 (for those born 1960 or later) — per SECURE 2.0, § 107.⁶

For qualifying see-through trusts, annual RMDs during the 10-year window are calculated using the Single Life Expectancy Table based on the oldest trust beneficiary's age in the year following the IRA owner's death, reduced by 1 for each subsequent year. The 10-year depletion deadline still applies: the full balance must be distributed regardless of how much has been taken through annual RMDs.

Implications for trusts:

• Conduit trust: Annual RMDs pass through to beneficiaries in the year received. Taxed at beneficiary rates. The trustee must ensure distributions are made in accordance with the trust's conduit language.
• Accumulation trust: Annual RMDs must be withdrawn from the IRA but can be retained in the trust. If retained, those amounts are immediately taxed at compressed trust brackets. The trustee must decide each year whether to pass distributions to beneficiaries or absorb the trust-level tax.

This annual RMD requirement applies to IRA owner deaths after December 31, 2019 where the decedent was past their RBD. For IRA owners who died before their RBD, trust beneficiaries are not required to take annual distributions — only full depletion by year 10.

What happens when a trust fails see-through

If a trust is named as IRA beneficiary but fails to meet see-through requirements, the IRA has no designated beneficiary (the trust entity doesn't count as a person for this purpose). The distribution timeline becomes less favorable — and depends on when the IRA owner died:⁷

The 5-year rule is highly compressed: a large inherited IRA must be fully distributed in 5 years rather than 10. For a high-income trust beneficiary, this can trigger maximum marginal tax rates across consecutive years — a severe outcome that proper trust drafting would have avoided.

Common reasons trusts fail see-through that estate attorneys identify during post-death review: including a charity as a potential beneficiary (even a remote remainder to charity), having a corporate trustee with an interest under certain trust structures, failing to include irrevocability-at-death language, and using pre-SECURE Act trust templates that referenced RMD rules that no longer exist as written.

T.D. 10001 and sub-trust separation — a new planning tool

One significant planning benefit introduced in the 2024 final regulations: a qualifying see-through trust can now be split into separate sub-trusts after the IRA owner's death, with each sub-trust establishing its own inherited IRA and using its own beneficiary's RMD options.²

Under prior regulations, this was not permitted — a trust with multiple beneficiaries was stuck using the oldest beneficiary's life expectancy factor for all of them. Now:

• A trust with three adult children as equal beneficiaries can divide into three sub-trusts, each establishing a separate inherited IRA
• Each sub-trust is evaluated independently — the 40-year-old and the 55-year-old sibling use their own Single Life Expectancy Table factors rather than both being stuck with the 55-year-old's shorter life expectancy
• If one beneficiary is an EDB (e.g., a disabled sibling), their sub-trust can use the stretch IRA while the others use the 10-year rule

This sub-trust separation must occur by December 31 of the year following the IRA owner's death to get separate accounting treatment. The mechanics require coordination between the trustee, an estate attorney, and the IRA custodian — each custodian has its own inherited IRA establishment procedures.

When naming a trust as IRA beneficiary still makes sense

The SECURE Act made trust-as-beneficiary strategies less tax-efficient for most situations. But there are cases where the non-tax benefits still justify the structure:

• Special needs beneficiary: A beneficiary receiving means-tested government benefits (Medicaid, SSI) can have their eligibility disrupted by a direct inherited IRA. A properly structured special needs trust, coordinated with a fee-only advisor and disability attorney, can preserve both the inheritance and the benefits. This requires careful drafting — the special needs trust must still meet see-through requirements.
• Minor children: Direct inherited IRAs require a guardian or custodian to manage for a minor. Naming a trust as beneficiary can give more control over distributions and the transition at majority. The conduit structure and the minor-child EDB rules (stretch until 21, then 10-year rule) can both be utilized if the trust is properly designed.
• Blended family situations: If the IRA owner wants to ensure an IRA benefits both a surviving spouse and children from a prior marriage, a qualified terminable interest property (QTIP) trust can be named as beneficiary — though the rules are complex and this is considered an advanced strategy.
• Spendthrift protection: If the beneficiary has creditor problems or substance abuse history, a conduit trust with spendthrift provisions can protect distributions that would otherwise be seized or squandered. The conduit structure ensures the distribution is taxed at the beneficiary's rate, not trust rates, while still providing protective terms.

In all these cases, the trust must be drafted by an attorney who understands the post-SECURE Act, post-T.D.-10001 environment. Many trusts on file at IRA custodians today were written before 2020 and haven't been reviewed since. The combination of changed law and unchanged trust documents is where problems arise.

Checklist: what to review if a trust is your inherited IRA beneficiary

1. Confirm see-through qualification. Review the trust against the three requirements: valid under state law, irrevocable at death, beneficiaries identifiable. If any fails, consult an estate attorney before taking distributions.
2. Identify conduit vs accumulation. Read the distribution provisions. Does the trust require immediate pass-through of all IRA proceeds, or does the trustee have discretion to accumulate? If accumulation, quantify the trust-bracket tax cost.
3. Check for non-individual beneficiaries. Search the trust document for any charitable gifts, nonprofit beneficiaries, or ambiguous class descriptions that could include a non-individual entity. These can destroy accumulation trust see-through status.
4. Determine RBD status of decedent. If the IRA owner died after their required beginning date, annual RMDs are required during the 10-year window. Confirm the first distribution year and calculate using the Single Life Expectancy Table for the oldest trust beneficiary.
5. Evaluate sub-trust separation. If multiple beneficiaries with different ages or EDB statuses are in the trust, consult with an estate attorney about whether separating into sub-trusts (by December 31 of the following year) creates better distribution options.
6. Document everything. Even though the October 31 custodian documentation requirement was eliminated for IRA trusts, keep copies of the trust document, beneficiary certification, and any sub-trust separation paperwork. You'll need it for RMD calculations and tax filings.

Sources

1. Treas. Reg. § 1.401(a)(9)-4, as amended by T.D. 10001 (July 18, 2024). See-through trust requirements: (1) valid under state law, (2) irrevocable or becomes irrevocable at owner's death, (3) beneficiaries identifiable from trust document. IRS Internal Revenue Bulletin 2024-33 (T.D. 10001).
2. T.D. 10001, July 18, 2024. Documentation requirement eliminated for IRA trusts: the trustee of a qualifying see-through trust is no longer required to provide trust documentation to the IRA custodian. Sub-trust separation rules for multiple beneficiaries also introduced. The October 31 documentation deadline continues to apply to employer-sponsored plan trusts (401(k), 403(b), etc.). Ed Slott and Company analysis: New Rules Loosen or Eliminate Documentation Rules for See-Through Trusts (irahelp.com). See also: Kitces.com — IRS Final Regulations: 10-Year Rule, Beneficiaries, RMDs.
3. Conduit vs. accumulation trust distinctions and "look-through" beneficiary determination: Treas. Reg. § 1.401(a)(9)-4(f) (conduit trusts) and § 1.401(a)(9)-4(f)(3) (accumulation trusts). Fidelity — Inherited IRA rules for trusts. Conduit vs. Accumulation Trust: SECURE Act & 10-Year Rule.
4. 2026 trust and estate income tax brackets per IRS Rev. Proc. 2025-32 and Form 1041-ES 2026: 10% on first $3,300; 24% on $3,301–$11,700; 35% on $11,701–approximately $16,000; 37% above approximately $16,000. Compare to 37% individual rate threshold of $626,350+ (single filer) in 2026. 3.8% NIIT applies to undistributed net investment income above the same trust threshold (~$16,000). IRS Form 1041-ES (2026). IRS Rev. Proc. 2025-32.
5. T.D. 10001, July 18, 2024. Annual RMD requirement for non-EDB beneficiaries (including qualifying trust beneficiaries) when decedent died after RBD, effective for distribution calendar years beginning on or after January 1, 2025. IRS — RMDs for IRA Beneficiaries.
6. SECURE 2.0 Act of 2022, § 107, amending IRC § 401(a)(9)(C): RBD is April 1 of the year following the year the IRA owner turns age 73 (for those born 1951–1959) or age 75 (for those born 1960 or later). IRS Publication 590-B (2025 edition).
7. IRC § 401(a)(9)(B) — no-designated-beneficiary rules: (i) pre-RBD death → 5-year rule (full distribution by December 31 of 5th year after death); (ii) post-RBD death → distributions must continue at least as rapidly as under the decedent's remaining life expectancy at death. IRC § 401(a)(9) (Cornell Law).

See-through trust requirements and T.D. 10001 rules verified against IRS Internal Revenue Bulletin 2024-33, Kitces.com analysis, and Ed Slott and Company guidance. Trust income tax bracket thresholds per IRS Rev. Proc. 2025-32 and Form 1041-ES 2026. Effective for distribution years beginning January 1, 2025.