RMD Aggregation Rule Multiple IRAs 2026 Calculator
The IRS IRA aggregation rule lets you compute RMDs across all Traditional IRAs and withdraw the total from any one — but 401(k)s and 403(b)s are calculated and distributed per account. Mixing them up triggers the 25% (10% if corrected) excise tax under SECURE 2.0.
| IRA Group (aggregation rule applies) | |
| IRA total balance | — |
| Aggregate IRA RMD (withdraw from any IRA) | — |
| 401(k) Accounts (per-account) | |
| 401(k) Account A RMD | — |
| 401(k) Account B RMD | — |
| 403(b) Accounts (aggregate within 403b) | |
| 403(b) RMD | — |
| Total 2026 RMD | — |
The IRS IRA aggregation rule (Reg §1.408-8 Q&A-9) lets you compute Required Minimum Distributions (RMDs) across all your Traditional IRAs and withdraw the total amount from any one IRA — you don't have to take a slice from each. However, 401(k)s and 403(b)s must each be calculated and distributed per account. Confusing the two triggers the SECURE 2.0 excise tax: 25% (reduced to 10% if corrected within the correction window).
IRA Aggregation Rule
Under Reg §1.408-8 Q&A-9, all of your Traditional IRAs are treated as one for RMD purposes. Add up the 12/31 prior-year balances of every Traditional, SEP, and SIMPLE IRA you own. Compute the total RMD using the appropriate life-expectancy table. Then withdraw that total from any combination of your IRAs. This is useful when one IRA has cash/short-term holdings and another holds illiquid investments — pull from the liquid IRA only. Inherited IRAs are aggregated separately from your own IRAs.
401(k) and 403(b) Rules Differ
401(k) plans: each plan's RMD must be calculated AND distributed from that specific plan. You cannot aggregate two 401(k)s, even with the same employer. 403(b) plans: can be aggregated among themselves — total all your 403(b) balances, compute one RMD, and withdraw from any 403(b). Cross-aggregation is NOT allowed: you cannot take your 401(k) RMD from an IRA, or vice versa. Each "bucket" stands alone.
The Uniform Lifetime Table
Per IRS Publication 590-B, most owners use the Uniform Lifetime Table. The 2022 table revision (effective 2022) lowered RMDs slightly — at age 75, the divisor is 24.6 (vs. 22.9 under the old table); at 80, 20.2; at 85, 16.0; at 90, 12.2. If your sole beneficiary is a spouse more than 10 years younger, use the Joint and Last Survivor Table instead (lower RMDs). The first RMD is required by April 1 of the year after you turn 73 (SECURE 2.0 set age 75 for those born 1960+).
SECURE 2.0 Penalty for Missed RMDs
Before SECURE 2.0, missing an RMD triggered a 50% excise tax. Now it's 25% — reduced to 10% if you correct within the "correction window" (by end of 2nd year following the missed RMD) and file Form 5329. Always file Form 5329 to report and request abatement. The IRS routinely waives the penalty for first-time mistakes with reasonable cause (e.g., death of CPA, serious illness). For aggregation mistakes (took total from wrong account type), the IRS typically waives — but document everything.
Last updated May 2026. Sources: IRS Publication 590-B, Reg §1.401(a)(9), SECURE 2.0 Act of 2022.