What a required minimum distribution is
Traditional retirement accounts are tax-deferred, not tax-free. You deducted the contributions or made them pre-tax, and the balance has grown untaxed ever since. The required minimum distribution is the point at which the government collects. Once you reach the starting age, you must withdraw at least a set fraction of the account each year and pay ordinary income tax on it.
The calculation itself is one division: your balance on December 31 of the prior year, divided by a life expectancy factor for your age. Everything difficult about RMDs is elsewhere — knowing whether you owe one this year, which table applies, which accounts count, and when exactly the deadline falls.
When yours begins
The SECURE 2.0 Act moved the starting age twice, so it now depends on when you were born:
- Born 1950 or earlier — began at 72, under the older rule.
- Born 1951 to 1959 — begins at 73.
- Born 1960 or later — begins at 75.
The 1959 birth year is genuinely ambiguous in the statute as written, which set up a conflict between 73 and 75. IRS proposed regulations resolve it at 73, and that is what this calculator uses.
The first year is the one that catches people
Your first distribution may be deferred to April 1 of the following year. That sounds like a favour and is often a trap: defer it and you take two distributions in the same calendar year, the deferred one and that year's own. Two distributions of taxable income in one year can push you into a higher bracket, raise the taxable share of your Social Security, and lift your Medicare premiums through IRMAA two years later.
Every year after the first has a hard December 31 deadline, with no deferral.
Which accounts count
Traditional IRAs, SEP and SIMPLE IRAs, and employer plans including 401(k), 403(b), and 457(b) all require distributions. Roth IRAs never have during the owner's lifetime, and since 2024 neither have designated Roth accounts inside a 401(k) or 403(b).
One practical wrinkle worth knowing: you may total the required amounts across all your IRAs and take the whole thing from any single one of them. Employer plans do not work that way — each 401(k) must be satisfied from that 401(k).
The cost of missing one
The excise tax is 25% of whatever you failed to withdraw, reduced to 10% if you correct it within two years. SECURE 2.0 halved this from the previous 50%, which was among the harshest penalties in the tax code. You report a missed distribution on Form 5329 and can request a waiver for reasonable cause, which the IRS does grant when the shortfall is corrected promptly.
IRS Uniform Lifetime Table
The factor falls as you age, so the required share of the balance rises every year. At 73 you withdraw about 3.8% of the account; by 90 it is around 8.2%.
| Age | Life expectancy factor | Share of balance |
|---|---|---|
| 73 | 26.5 | 3.77% |
| 75 | 24.6 | 4.07% |
| 77 | 22.9 | 4.37% |
| 80 | 20.2 | 4.95% |
| 82 | 18.5 | 5.41% |
| 85 | 16.0 | 6.25% |
| 87 | 14.4 | 6.94% |
| 90 | 12.2 | 8.20% |
| 92 | 10.8 | 9.26% |
| 95 | 8.9 | 11.24% |
| 100 | 6.4 | 15.63% |
Full table runs from 72 to 120+ in IRS Publication 590-B, Appendix B, Table III. It is a mortality table rather than an inflation-adjusted figure, so it does not change annually — the current version took effect in 2022.
Frequently asked questions
At what age do required minimum distributions start?
Age 73 if you were born between 1951 and 1959, and age 75 if you were born in 1960 or later. The SECURE 2.0 Act raised the age from 72 in stages. Your first distribution is for the year you reach that age, and you may defer only that first one to April 1 of the following year.
How is a required minimum distribution calculated?
Take your account balance on December 31 of the prior year and divide it by the life expectancy factor for your age from the IRS Uniform Lifetime Table. At age 75 the factor is 24.6, so a $500,000 balance requires $20,325.20. The balance used is always the prior year-end figure, not the current one.
Do Roth accounts require minimum distributions?
No, not during the owner’s lifetime. Roth IRAs have never required them, and the SECURE 2.0 Act removed them from designated Roth accounts in 401(k) and 403(b) plans starting in 2024. Beneficiaries who inherit a Roth account do face distribution rules.
What is the penalty for missing a required minimum distribution?
A 25% excise tax on the amount you failed to withdraw, reduced to 10% if you correct the shortfall within two years. The SECURE 2.0 Act cut this from the previous 50%. You report and request a waiver on IRS Form 5329, and the IRS does waive it for reasonable cause that is promptly corrected.
Which accounts require minimum distributions?
Traditional IRAs, SEP IRAs, SIMPLE IRAs, 401(k), 403(b), 457(b), and other defined contribution plans. Roth IRAs and designated Roth accounts are exempt during the owner’s lifetime. IRA distributions can be aggregated and taken from any one IRA, and 403(b) balances can likewise be combined, but each 401(k) or other employer plan must be satisfied separately.
Does having a younger spouse change the amount?
Yes, if your spouse is your sole beneficiary and is more than 10 years younger. That situation uses the IRS Joint Life and Last Survivor Table rather than the Uniform Lifetime Table, which produces a longer distribution period and therefore a smaller required amount. The joint table depends on both ages, so check Table II in IRS Publication 590-B.