Calculate each account separately, then reconcile the group

IRS Form 5329 instructions allow certain inherited IRA RMDs to be satisfied across inherited IRAs from the same decedent. The useful workflow is to calculate each account separately first, then reconcile the eligible group after distributions post. This page turns that rule into a year-by-year worksheet.

Step 1: create one row per inherited IRA

AccountDecedentPrior Dec. 31 balanceDenominatorCalculated RMD
Inherited IRA AMother$240,00030.0$8,000
Inherited IRA BMother$120,00030.0$4,000
Same-decedent totalMother——$12,000

Do not start by adding the balances together. The account-level RMD calculation stays visible even when the resulting minimums may later be satisfied from one or more eligible accounts.

Step 2: record where the cash actually came from

Distribution dateSource accountGross amountSame-decedent group credited
March 15Inherited IRA B$5,000Mother
September 20Inherited IRA A$7,000Mother
Total credited—$12,000Mother

In this example, the $12,000 group minimum is satisfied even though the withdrawals did not mirror the $8,000/$4,000 account-level calculations. The worksheet still preserves those calculations for audit and reconciliation.

Step 3: reconcile before year end

Add the gross distributions that are eligible to satisfy the same-decedent inherited-IRA group and compare them with the calculated group minimum. Do not use withholding-net amounts. If a $5,000 gross distribution had $500 withheld, the distribution is still $5,000 for the retirement-account distribution record.

Step 4: carry forward each account separately

Aggregation does not merge the accounts for next year’s math. Each inherited IRA still has its own December 31 balance, transfer history, basis records, and tax form. For the next calendar year, update every row with the new year-end balance and the denominator required for that account.

Three-year worksheet structure

YearIRA A RMDIRA B RMDGroup minimumGross distributions creditedShortfall
2027CalculateCalculateA + BReconcile0 or amount due
2028RecalculateRecalculateA + BReconcile0 or amount due
2029RecalculateRecalculateA + BReconcile0 or amount due

The point is to prevent a valid aggregation rule from becoming a reason to stop doing account-level calculations.

Aggregation is permitted, not required — which account you draw from is a choice

The same-decedent rule lets a beneficiary satisfy the group minimum from one or more of the eligible accounts, but it does not force a particular source. A beneficiary who wants to keep one inherited account invested longer can take the full group RMD from the account they intend to spend down first, as long as the gross distributions credited to the group meet the calculated total. Record which account actually paid, because the tax form follows that account.

Choose the paying account on purpose

A beneficiary can satisfy the group minimum from one or more eligible accounts, for example from the account they plan to spend down first. Record which account actually paid, because the tax form follows that account.

Keep Roth inherited IRAs in their own permitted group

Form 5329 instructions separately address inherited Roth IRAs from the same decedent. Do not assume a traditional inherited IRA distribution can satisfy an inherited Roth IRA obligation simply because the decedent is the same. Label the tax category in the worksheet before grouping accounts.

Choose the source for a same-decedent RMD
Are the accounts in the same permitted decedent and tax category group?
Yes
Eligible gross distributions from one or more accounts may satisfy the group minimum. Record the account that paid.
No
Keep the accounts in separate groups. A distribution from one group does not satisfy the other group's RMD.

Or skip the worksheet: consolidate same-decedent accounts into one

Aggregation is a way to manage multiple accounts, but a beneficiary can also eliminate the bookkeeping by combining them. Two inherited traditional IRAs from the same decedent can be merged into a single inherited IRA by trustee-to-trustee transfer, as long as the surviving registration keeps the decedent and beneficiary identifiers. After consolidation there is one balance, one denominator, and one RMD. The limits still apply: a traditional inherited IRA cannot be merged with an inherited Roth, and accounts from different decedents must stay separate.

Do not add the beneficiary’s own IRA or another decedent

A nonspouse inherited IRA is not the beneficiary’s personal IRA. Likewise, an inherited IRA from a father belongs to a different decedent group than an inherited IRA from a mother. Use one worksheet tab per decedent and keep the beneficiary’s own IRAs outside those inherited groups.

Year-end closeout checklist

  • Account-level RMD calculation saved for every inherited IRA.
  • Decedent name and date of death shown on every row.
  • Gross distributions reconciled to custodian confirmations.
  • Same-decedent group minimum fully satisfied.
  • Traditional and Roth inherited groups not mixed.
  • December 31 balances saved for next year.
  • Year-10 deadline retained even if one account was emptied.

That is the practical difference between merely knowing the aggregation rule and having records that prove the rule was applied correctly.