IRS Publication 590-B · Beneficiary Rule Logic · June 2026
An inherited IRA RMD calculator should not start with age alone. It should start with the IRS beneficiary rules — especially whether the account is subject to the SECURE Act 10-year rule or an annual life-expectancy method using IRS Publication 590-B. For many beneficiaries subject to the 10-year rule, the key requirement is full distribution by the end of year 10; for others, annual distributions apply using the prior year-end balance divided by the IRS factor.
A useful inherited IRA RMD calculator has to do more than divide a balance by a number. It has to first figure out which IRS rule applies based on the beneficiary type and the original owner's death year. If that rule is wrong, the output can be wrong even if the arithmetic is perfect.
The calculator logic should answer three questions first:
A generic "RMD calculator" often misses these points. Inherited IRAs are not the same as a typical owner RMD. The IRS treats beneficiary distributions differently, and the result can be a final-year clean-out rather than a steady annual withdrawal schedule.
Inherited IRA RMDs depend on beneficiary classification and timing. For many non-spouse designated beneficiaries inheriting after 2019, the default outcome is often the SECURE Act 10-year rule, which generally requires full distribution by the end of year 10. That final deadline can coexist with annual RMDs when the applicable beneficiary and RBD facts require them. Spouses and certain eligible designated beneficiaries can follow different timelines or methods.
| Category | Default path |
|---|---|
| Spouse | Special rules; may treat as own IRA or keep as inherited |
| Eligible designated beneficiary (EDB) | Life-expectancy-based schedule may apply; verify EDB criteria |
| Non-eligible designated beneficiary | Often subject to 10-year rule |
| Estate, trust, or non-designated | More complex — may need tax professional |
The rule path depends on the owner's death year and, in some cases, whether the owner died before or after their required beginning date. The start timing can change the schedule. That is why a calculator should require the original owner's death year before showing a result.
For life-expectancy-based inherited IRA methods where a specific IRS factor applies, the RMD is generally computed by dividing the prior year-end balance by the distribution period from the applicable Publication 590-B table for that method.
RMD = prior year-end account balance ÷ distribution period
The hard part is selecting the right distribution period from the right IRS table. The calculator should show which table it used and which version of the publication it relied on.
For annual RMD math, the IRS generally uses the December 31 balance from the prior year. That means a current-day balance is not always the right number to use. A calculator should either ask for the prior-year-end balance directly, or clearly explain how to map a custodian statement to the IRS timing rule.
Under the SECURE Act 10-year rule, many beneficiaries must have the inherited IRA fully distributed by the end of year 10. The final deadline does not by itself answer whether annual RMDs are also due in earlier years; that depends on beneficiary category and whether the original owner had reached their required beginning date.
A calculator may show $0 for an annual RMD only when the stated facts and applicable IRS rules mean no annual amount is due for that year. It should not infer that result from the ten-year rule alone. A valid output may show:
The ten-year deadline and any annual RMD requirement must be displayed separately.
For 10-year-rule scenarios, the output should make this clear:
A good inherited IRA RMD calculator should output a year-by-year schedule. That helps users see whether they are dealing with annual withdrawals or a final clean-out deadline.
| Calendar year | Rule applied | RMD due | Notes |
|---|---|---|---|
| Years 1–9 | 10-year rule | Depends on facts | Annual RMDs may coexist with the ten-year deadline |
| Year 10 | 10-year rule | Full remaining balance | Final clean-out deadline: Dec. 31 of year 10 |
In a qualifying 10-year-rule scenario, the calculator may show $0 annual minimums for a specific period while still requiring the account to be fully distributed by the end of year 10. That result depends on the beneficiary classification, the owner’s RBD status, and the applicable IRS guidance.
Expected output pattern:
When an inherited IRA qualifies for an annual life-expectancy approach, the calculator generally divides the prior-year-end balance by the correct distribution period from IRS Publication 590-B.
| Input | Example value |
|---|---|
| Prior year-end balance | $150,000 |
| Distribution period (IRS factor) | 22.0 |
| Annual RMD | $6,818.18 |
Using the wrong version of Publication 590-B can change the result.
A 10-year-rule account is not the same as an annual life-expectancy account.
The IRS timing rule generally uses the prior December 31 balance for annual calculations.
Age alone is not enough to determine the result.
A $0 annual amount does not mean "no action required." The 10-year final deadline still exists.
For taxable years beginning after December 29, 2022, the IRS excise tax for a missed RMD is generally 25% of the shortfall. It can be reduced to 10% if corrected within the IRS correction window. That is why using the correct formula matters before a deadline approaches.
An under-distribution based on a wrong calculation is not treated differently than a deliberate miss when the IRS applies the excise tax. The beneficiary is responsible for getting the right amount, not just relying on the custodian's worksheet.
It should identify the IRS rule category — specifically whether the beneficiary is under the SECURE Act 10-year rule or an annual life-expectancy method. Using the wrong rule can produce an incorrect result even if the arithmetic is perfect.
For life-expectancy-based inherited IRA methods, IRS guidance commonly points to the Single Life Expectancy Table (Table I) in Publication 590-B. The correct table depends on the beneficiary situation — multiple beneficiaries and trust situations may require different methods.
A $0 result can be correct only when the beneficiary category, owner RBD status, and applicable IRS rules mean no annual minimum is due for that year. The 10-year final deadline still applies, and annual RMDs can coexist with it for some beneficiaries.
For annual RMD math, the IRS generally uses the December 31 balance from the prior year. A current-day balance is not the right number to use for the calculation. Always use the prior year-end statement.
An under-distribution can trigger a 25% excise tax on the shortfall, reduced to 10% if corrected within the IRS correction window. That is why using the correct balance, the correct table, and the correct rule path matters.