TL;DR: An RMD calculator determines the minimum amount you must withdraw annually from most tax-deferred retirement accounts once you reach a certain age.
- Your RMD is calculated by dividing the prior year's December 31 account balance by an IRS life expectancy factor.
- The current starting age for RMDs is 73 for those born between 1951 and 1959.
- The primary IRS table used for this calculation is the Uniform Lifetime Table.
- Failing to take the full RMD can result in a tax penalty of up to 25% of the shortfall.
- RMDs apply to Traditional IRAs, SEP IRAs, SIMPLE IRAs, 401(k)s, and 403(b)s, but not Roth IRAs for the original owner.
What Is a Required Minimum Distribution (RMD)?
A Required Minimum Distribution (RMD) is the legally mandated minimum amount you must withdraw each year from most tax-deferred retirement accounts after reaching a specific age. The rule exists so that the government can collect taxes on funds that have grown tax-deferred for decades. These distributions are treated as ordinary income and are subject to income tax in the year they are withdrawn.
RMD rules apply to a variety of retirement plans. These include Traditional IRAs, SEP IRAs, and SIMPLE IRAs. They also apply to employer-sponsored retirement plans like 401(k), 403(b), and 457(b) plans. While Roth 401(k)s are subject to RMDs, Roth IRAs are a notable exception; original account owners are not required to take RMDs from their Roth IRAs during their lifetime.
How Does an RMD Calculator Work?
An RMD calculator computes your required annual withdrawal using a simple formula: it divides your retirement account's balance from the end of the previous year by a life expectancy factor provided by the IRS. This calculation ensures you withdraw a proportional amount of your savings over your estimated remaining lifespan.
To use a typical RMD calculator, you must provide three key pieces of data:
- Your Date of Birth: This is used to determine your age for the distribution year.
- Prior Year-End Account Balance: The calculator needs the total fair market value of your retirement account(s) as of December 31 of the preceding year.
- Beneficiary Information: For most individuals, this is not a factor. However, if your sole beneficiary is a spouse who is more than 10 years younger than you, a different IRS table is used, which results in a smaller RMD.
What Is the RMD Starting Age?
The age at which you must begin taking RMDs is 73 if you were born between 1951 and 1959. This age has changed multiple times due to legislation, most recently the SECURE 2.0 Act of 2022. The specific starting age depends entirely on your birth year.
The schedule for beginning RMDs is tiered based on birth date.
| If You Were Born... | Your RMDs Begin at Age... |
|---|---|
| Before July 1, 1949 | 70 ½ |
| July 1, 1949 - 1950 | 72 |
| 1951 - 1959 | 73 |
| 1960 or later | 75 |
An important exception exists for employer-sponsored plans like 401(k)s. If you are still working for the company that sponsors the plan, are not a 5% owner of the company, and the plan allows it, you may be able to delay RMDs from that specific plan until you retire.
Which IRS Life Expectancy Table Should You Use?
Most retirement account owners use the Uniform Lifetime Table to find the life expectancy factor needed to calculate their RMD. This is the default and most common table for account owners who are unmarried or whose spouse is not more than 10 years younger. The IRS provides different tables for specific situations.
The appropriate table selection is critical for an accurate RMD calculation.
| Table Name | When to Use |
|---|---|
| Uniform Lifetime Table | The standard table for nearly all account owners. It's used if you are unmarried, or if your spouse is not more than 10 years younger than you. |
| Joint and Last Survivor Table | Used only if your spouse is your sole beneficiary and is more than 10 years younger than you. Using this table results in a larger life expectancy factor and a smaller RMD. |
| Single Life Expectancy Table | This table is generally used by beneficiaries who have inherited a retirement account. |
What Happens If You Miss an RMD?
Failing to withdraw the full Required Minimum Distribution by the annual deadline results in a substantial tax penalty. The penalty, also known as an excise tax, is applied to the amount of the RMD that was not withdrawn on time. This is one of the steepest penalties imposed by the IRS.
Under the SECURE 2.0 Act, the penalty for a missed RMD was reduced from 50% to 25% of the shortfall. The penalty can be further reduced to 10% if you correct the mistake by withdrawing the required amount and filing the appropriate tax form within a specific correction window. You can request a waiver for the penalty by filing IRS Form 5329 and explaining that the shortfall was due to a reasonable error.
Frequently Asked Questions
How do I figure out my RMD amount? To calculate your RMD, take your retirement account's fair market value from December 31 of the previous year and divide it by the life expectancy factor found in the appropriate IRS table for your age.
What is the RMD percentage at age 73? At age 73, the life expectancy factor in the Uniform Lifetime Table is 26.5. This corresponds to a withdrawal of approximately 3.77% of the account's prior year-end balance (1 divided by 26.5).
How much would the RMD be on $500,000? For a 73-year-old, the RMD on a $500,000 account balance would be $18,867.92. This is calculated by dividing $500,000 by the life expectancy factor of 26.5.
What are the new RMD age tables? The IRS updated its life expectancy tables, including the Uniform Lifetime Table, starting in 2022 to reflect longer life expectancies. These updated tables feature larger distribution periods (life expectancy factors), which generally result in slightly smaller RMDs compared to the old tables.
Do I have to take RMDs from a Roth IRA? No, the original owner of a Roth IRA is not required to take any RMDs during their lifetime. However, beneficiaries who inherit a Roth IRA are typically required to take distributions according to specific rules.