Rules current as of September 2026. Informational only; not tax, legal, or investment advice.
Most people compute their RMD with the Uniform Lifetime table. There is a second table, and if it applies to you, your RMD is smaller every year for the rest of your life.
It applies when two things are true for the whole year: your spouse is more than ten years younger than you, and your spouse is the sole primary beneficiary of the account. Then you use the Joint Life and Last Survivor Expectancy table, which the IRS calls Table II and prints as Appendix B of Publication 590-B.
What "more than ten years younger" means
The test is birthdays in the distribution year, not exact ages. You're 73 on December 31 and your spouse is 55 on December 31: eighteen years, Table II applies. You're 73 and your spouse turns 63 that year: ten years exactly, not more than ten, Uniform table.
"Sole beneficiary for the entire year" is strict. If you named your spouse and a child as co-beneficiaries, or the account passes to a trust, the Uniform table applies. The one exception is death or divorce during the year: if your spouse was the sole beneficiary on January 1 and you divorce in June, you still use Table II for that year.
How to read Table II
Table II is a grid. Owner's age runs down the side, spouse's age across the top, and the number where they meet is your divisor. Use each person's age as of December 31 of the year the RMD is for.
The divisor is always larger than the Uniform Lifetime factor for the same owner age, because it's based on two lives instead of one. Larger divisor, smaller RMD.
Worked example
Owner turns 73 in 2026. Spouse, sole beneficiary, turns 55. IRA balance on December 31, 2025: $1,000,000.
Uniform Lifetime table, age 73: 26.5. RMD $37,735.85.
Table II, ages 73 and 55: 32.6. RMD $30,674.85.
The difference is $7,061.00 this year, and it recurs annually because both factors shrink slowly and the Table II factor stays ahead. Over ten years on a balance that size, it's tens of thousands of dollars that stays in the account.
Where calculators go wrong
This is the rule most people assume calculators mishandle. In our test of 21 public RMD calculators this summer, 16 got it exactly right. Three had no spouse input at all and said so. One returned the wrong number because it used the spouse's age on the day you ran it instead of at year-end, understating the RMD for anyone whose spouse hadn't had a birthday yet; the company fixed it after we reported it. And one of the three with no spouse field was ours. We added it in September.
If a calculator never asks for your spouse's birthdate, it can only give you the Uniform Lifetime answer, which for a Table II household overstates the RMD. Overstating isn't penalized, but it's money out of a tax-deferred account earlier than the law requires.
The steps
Confirm both conditions on December 31 of the RMD year: spouse more than ten years younger, spouse sole primary beneficiary. Check the beneficiary designation on file with the custodian, not your memory of it.
Take the account balance from the December 31 statement for the prior year.
Find the divisor in Table II at your age and your spouse's age. Publication 590-B, Appendix B, Table II.
Divide. That's the RMD for this account.
If you have more than one IRA, do this for each; the Table II test is per account, because the beneficiary designation is per account. IRA RMDs can then be pooled and taken from any one of them.
Want the Table II factor looked up for you? The SimpleRMD calculator accepts a spouse birthdate and a sole-beneficiary confirmation, applies Table II when it should, and shows the table, the factor, and the regulation behind the result so you can check it against Publication 590-B.
Rules cited: 26 CFR §1.401(a)(9)-9(b) (Uniform Lifetime) and §1.401(a)(9)-9(d) (Joint and Last Survivor); 26 CFR §1.401(a)(9)-5(c)(2) (sole-beneficiary-for-the-year rule); IRS Publication 590-B, Appendix B, Table II. Your situation may differ; confirm with a qualified professional. Version 1.0, September 2026.