RMD Aggregation Rules: Which Accounts Can Be Combined?

If you have multiple retirement accounts, you don't necessarily have to take a separate distribution from each one. The IRS allows aggregation for some account types — but not others. Getting this wrong means either over-distributing (paying unnecessary tax) or under-distributing (triggering a 25% penalty). Here's exactly how the rules work.

What aggregation means — and why it matters

Each retirement account technically has its own RMD — calculated by dividing the prior December 31 balance by the applicable IRS life-expectancy divisor. "Aggregation" means you can add up the RMDs from multiple accounts in the same category and satisfy them all by taking the total from just one or two accounts in that group.

Why does this matter? Three reasons:

• Investment flexibility. You can choose which account to deplete — allowing strategic choices about asset location, tax lot harvesting, and which investments to liquidate.
• Simplicity. Rather than coordinating distributions from five IRAs, you take one distribution from the account you want to draw down.
• Tax sequencing. Taking from an account that holds lower-basis assets, or that will otherwise generate lower taxes, can reduce your lifetime tax bill.

But aggregation only works within specific account-type categories. Cross the wrong line — pulling 401(k) RMD from an IRA, for example — and you've still failed to satisfy the 401(k) requirement, regardless of how much you took from the IRA.

Traditional IRAs: full aggregation permitted

The most flexible category. All of your own traditional IRAs — including SEP IRAs, SIMPLE IRAs, and rollover IRAs — can be aggregated for RMD purposes.¹

Example: You have three traditional IRAs with December 31 balances of $800,000, $400,000, and $200,000. Using the Uniform Lifetime Table at age 76 (divisor: 23.7), your RMDs are approximately $33,755, $16,878, and $8,439 — a total of $59,072. You can satisfy this entirely by taking $59,072 from IRA #1 and leaving the other two untouched.

This is useful if one IRA holds assets you don't want to liquidate (e.g., a specific bond ladder, a concentrated equity position you're managing the tax basis of). Take from the flexible account; leave the strategic one intact.

One exception: Inherited IRAs are NOT aggregated with your own IRAs. They're a separate pool — see below.

401(k) plans: no aggregation — each plan distributes separately

Unlike IRAs, 401(k) plans (and other defined contribution employer plans — 403(a), 457(b)) require RMDs to be calculated and taken separately from each plan.¹ You cannot calculate the total and satisfy it from a single plan.

If you have 401(k) accounts at multiple former employers, you must take RMDs from each one independently. This is the most common aggregation trap — people assume the rules work the same as IRAs.

The practical fix: Roll old 401(k) balances into a traditional IRA. Once the balance is in the IRA, it joins the IRA aggregation pool — simplifying your RMD math to a single calculation. There are situations where keeping a 401(k) makes sense (ERISA creditor protection, NUA strategies, certain employer stock situations), but from a pure RMD-simplification standpoint, IRA rollover consolidates the complexity. See our complete RMD guide for rollover timing considerations.

403(b) accounts: aggregation within the 403(b) category

403(b) plans have their own aggregation rule, separate from both IRAs and 401(k)s.¹ If you have multiple 403(b) accounts, you can aggregate them and satisfy the total from one 403(b). But 403(b) RMDs cannot be satisfied from an IRA, and IRA RMDs cannot be satisfied from a 403(b).

Source: IRS RMD Comparison Chart (IRAs vs. defined contribution plans).¹

Inherited IRA aggregation: same decedent only

If you inherited multiple IRAs from the same person, you may aggregate those accounts — calculate the individual RMDs and take the total from any one of them. This is the same rule as for your own IRAs, but scoped to the same decedent.²

You cannot aggregate inherited IRAs from different people. If you inherited accounts from your father and from your mother, those are two separate pools requiring separate RMDs. And you cannot combine inherited IRA RMDs with your own IRA RMDs — they're different pools entirely.

For inherited IRAs subject to the 10-year rule (SECURE Act — non-spouse beneficiaries inheriting after 2019), annual RMDs may be required when the decedent had already begun RMDs (T.D. 10001 finalized July 2024). The aggregation option still applies within the inherited pool from a single decedent. See our inherited IRA 10-year rule page for distribution strategy.

The still-working exception: delay 401(k) RMDs from your current employer

There is one important exception to the rule that 401(k) RMDs begin at age 73: if you're still employed at the company sponsoring the plan and you own less than 5% of the business, you can delay RMDs from that specific plan until you actually retire.³

This does NOT delay IRA RMDs. Many people working into their mid-70s assume their IRA RMDs are also deferred. They're not. IRA RMDs begin at age 73 regardless of employment. Only the current employer's qualified plan gets the delay — and only if the plan document allows it (most do, but confirm with your HR department or plan document).

The still-working exception is most relevant for:

• Physicians, attorneys, and consultants still in active practice in their 70s
• Business executives with significant 401(k) balances who plan to work until 75+
• Part-time employees past 73 whose primary tax-deferred wealth is in the current employer plan

For small business owners: if you own 5% or more (or if your spouse's ownership plus yours aggregates above 5%), the still-working exception does not apply — you must take RMDs from the plan at the normal age.

Roth accounts: no lifetime RMDs

Roth IRAs have never had lifetime RMDs for the original owner. Your beneficiaries will eventually face distribution rules, but during your lifetime, Roth IRA balances are not subject to required distributions — no calculation, no penalty risk.

Starting 2024, Roth 401(k) and Roth TSP accounts joined Roth IRAs in having no lifetime RMDs. SECURE 2.0 Act § 325 eliminated this requirement.⁴ This closed a meaningful gap — previously, Roth 401(k) owners had to take RMDs (or roll to a Roth IRA before the RMD age to avoid them). That workaround is no longer necessary.

If you have a Roth 401(k) balance, you can now leave it indefinitely without RMD risk. The asset continues to grow tax-free; there's no timing pressure from the distribution rules.

Strategic implications: simplifying your RMD picture

The aggregation rules create an argument for consolidation that's purely administrative — but administrative simplicity has real value when you're managing multiple accounts across multiple custodians in your 70s and 80s.

Rolling old 401(k)s to a traditional IRA is the most impactful simplification move. Once consolidated, you go from "take from each plan separately" to "calculate once, take from one account." The RMD discipline becomes: one calculation, one transaction, one record-keeping step per year.

Considerations before rolling a 401(k) to an IRA:

• Creditor protection. 401(k) plans have unlimited ERISA creditor protection in most states; traditional IRAs have more limited and state-law-dependent protection. If you have significant liability exposure (practicing physician, business owner), consult an attorney before rolling.
• Net Unrealized Appreciation (NUA). If your 401(k) holds highly appreciated employer stock, NUA rules may allow a tax-advantaged distribution. Rolling to an IRA forfeits this.
• Still-working exception. If you may use the still-working exception with this plan, a rollover at 72 forfeits that option. Keep the plan intact until retirement if the delay has significant tax value.
• Roth 401(k) balances. Roll to a Roth IRA (not a traditional IRA). Keeping them in the plan is now fine given no lifetime RMD requirement, but rolling out preserves flexibility for beneficiaries.

What an advisor models that you can't easily do alone

RMD aggregation rules are straightforward to describe but complex to optimize across a real portfolio. An RMD specialist will:

• Map all accounts to the correct aggregation pools (IRA, 403(b), each employer plan, inherited)
• Identify which 401(k) accounts are candidates for IRA rollover vs. retention
• Model whether the still-working exception creates material tax deferral worth preserving
• Determine the optimal IRA account to deplete each year (tax lot, asset-location, heir-value considerations)
• Coordinate the distribution schedule with QCDs, Roth conversions, and Social Security timing

With $1M+ in tax-deferred accounts, getting this wrong is expensive. Use our RMD Calculator to see your projected RMDs across the next decade, and consider whether your current distribution approach is optimized.

Sources

1. IRS — RMD Comparison Chart: IRAs vs. Defined Contribution Plans. Aggregation rules: IRAs can aggregate and satisfy from one account; 403(b)s can aggregate within the 403(b) category; 401(k) and other employer plans must each distribute separately.
2. IRS Publication 590-B — Distributions from Individual Retirement Arrangements (2025). Inherited IRA aggregation: RMDs from multiple inherited IRAs from the same decedent may be aggregated and taken from one of those accounts.
3. IRS — Retirement Plan and IRA Required Minimum Distributions FAQs. Still-working exception: participants in a workplace plan who are not 5%-or-more owners can delay RMDs from that plan until actual retirement.
4. IRS — Retirement Topics: Required Minimum Distributions. SECURE 2.0 Act § 325: Roth 401(k) and Roth TSP accounts no longer subject to lifetime RMDs for the original account owner, effective for tax years beginning after December 31, 2023.

Aggregation rules verified against IRS Publication 590-B and IRS RMD Comparison Chart, April 2026. Rules are governed by final Treasury regulations; a qualified advisor should review your specific account structure before relying solely on general rules.