Retirement can feel like it moves in chapters. In your 60s, the focus might be on when to stop working and how to claim Social Security. In your early 70s, taxes often take center stage, especially once required minimum distributions (RMDs) begin.
If you have money in traditional IRAs, SEP/SIMPLE IRAs, or many employer retirement plans, the IRS generally requires you to start taking taxable withdrawals each year. The rules are specific, the math must be right, and the stakes can be meaningful.
Here is the part many people miss: even if your financial institution calculates an RMD amount for you “as a courtesy,” you are ultimately responsible for taking the correct RMD on time. Custodians do not always have the full picture, particularly when your money moved during the year or your account situation changed.
Below is a practical, client-friendly guide to the core RMD calculation, plus the common “extra math” situations that can cause otherwise careful retirees to accidentally under-distribute.
First: A quick RMD refresher (what it is and why it matters)
An RMD is the minimum amount the IRS generally requires you to withdraw from certain retirement accounts each year after you reach the applicable age. Most RMDs are taxed as ordinary income, and they can:
- Increase your taxable income
- Affect Medicare premium brackets (IRMAA)
- Influence how much of your Social Security is taxable
- Change your tax bracket and the tax efficiency of your portfolio withdrawals
That does not mean RMDs are “bad.” It just means they are a predictable tax event that deserves a plan.
Important note: RMD rules have changed in recent years. Your required starting age depends on your birth year and current law. If you are unsure whether your RMDs begin at 73 or later, confirm with your tax professional or financial advisor.
The basic RMD calculation: two steps
For most retirees, RMD math boils down to two steps.
Step 1: Find your account value as of December 31
Typically, this is the value shown on your year-end statement for the prior calendar year.
For example, if you are calculating your RMD for 2026, you will generally use your retirement account value as of December 31, 2025.
Step 2: Divide by the correct IRS life expectancy factor
You look up your life expectancy factor on the appropriate IRS table, then divide.
RMD = 12/31 account value ÷ life expectancy factor
That is the formula.
But the details matter because “your 12/31 account value” is not always as simple as what appears on a single statement, and the “appropriate IRS table” is not always the default one.
Why custodian-calculated RMDs can be wrong (even when everyone means well)
Many custodians provide an RMD calculation to clients automatically. For most people, those numbers are directionally right and often correct.
However, custodians only calculate based on what they can see inside their own system.
- They may not know about assets “in motion” between institutions.
- They may not know you recharacterized a contribution.
- They may not know a QLAC correction is required.
- They may default you to the wrong life expectancy table if your beneficiary situation changed.
And here is the key risk: tax courts have generally held that the taxpayer is responsible for taking the correct RMD, even if you relied on a custodian’s estimate.
So the goal is not to distrust your custodian. It is to verify whether your situation had any wrinkles that could make the usual calculation incomplete.
The biggest “extra math” issue: money that was “in motion” near year-end
One of the most common trouble spots happens when funds move late in the year, especially rollovers around the New Year.
A real-world scenario
Imagine someone retires and begins a rollover process in December. A 401(k) plan might cut a rollover check made payable to the IRA custodian (often with “FBO” language). That check can take time to mail and deposit.
Here is where confusion starts.
- On December 31, the IRA might show a balance of $0 because the rollover has not arrived yet.
- The 401(k) might also show $0 because the money left the plan.
If you only look at statements, it can appear as though you had no balance at year-end, so maybe no RMD is due.
But the IRS does not treat this as a loophole.
The practical rule of thumb
If money left one retirement account before year-end and had not landed in the new retirement account by December 31, you may need to add that “in motion” amount back when determining the relevant year-end value for RMD purposes.
This is exactly the kind of situation a custodian often cannot see. Each institution can only see its own slice of the transaction.
Who is most at risk?
- Retirees who separate from service late in the year
- Anyone consolidating accounts across multiple custodians
- People doing “cleanup” rollovers after leaving an employer
- Couples coordinating rollovers while also managing beneficiary updates
How to reduce the risk
If you rolled money over in November, December, or early January:
- Keep rollover paperwork and dates (distribution date, check date, deposit date).
- Save year-end statements from both institutions.
- Ask your advisor or tax professional whether any “in motion” adjustment is needed before you assume the statement balance tells the whole story.
Second “extra math” situation: Roth IRA recharacterizations
A recharacterization can be a legitimate fix when someone contributes to a Roth IRA and later discovers they were not eligible because income exceeded the limit.
In many cases, people do not realize this until tax time the following year, when a CPA flags the issue and recommends recharacterizing the contribution into a traditional IRA.
Why this affects RMD math
When a Roth contribution is recharacterized, the transaction is treated as though the contribution had been made to the traditional IRA from the beginning. That means the amount typically needs to be reflected appropriately when determining the year-end value used for calculating an RMD.
It is not just the original contribution amount. Depending on the timing and how the recharacterization is processed, related gains or losses can also affect what must be included.
Why custodians miss it
Your custodian may show the recharacterization clearly inside one account, but RMD calculations may still default to standard year-end balances without accounting for the recharacterized amounts in the specific way the rules require.
What to do if this happened
If you recharacterized a Roth contribution (or even explored it and are not sure how it was processed), it is worth a quick review with your advisor and tax professional to confirm your RMD base is not understated.
Third “extra math” situation: QLAC overpayments
A qualifying longevity annuity contract (QLAC) is a type of longevity-focused income annuity that can be purchased inside certain retirement accounts. Done correctly, it may reduce the portion of your account that is subject to RMD calculations up to certain limits.
But if someone contributes more than allowed to a QLAC, the excess amount may need to be included back in the RMD calculation.
Why this matters
Because QLAC rules are limit-driven, an “overpayment” can create a mismatch between what you think is excluded from RMD calculations and what the IRS actually requires.
The practical takeaway
If you bought a QLAC (or adjusted one) in recent years, confirm:
- How much was allocated
- Whether it stayed within the allowable limits
- Whether there was any correction process for an excess amount
This is another area where a custodian’s standard RMD estimate may not fully reflect the nuance.
Choosing the right life expectancy table: the part many people never revisit
Once your December 31 value is correct, you still need the correct life expectancy factor.
The IRS has three different life expectancy tables, and choosing the wrong one can change your RMD and therefore your taxable income.
1) Uniform Lifetime Table (the default for most people)
Most account owners use the Uniform Lifetime Table. If nothing special applies, this is typically the table.
This is why many custodians default to it.
2) Joint Life and Last Survivor Table (for a specific spouse-beneficiary scenario)
You can generally use the Joint Life and Last Survivor Table only if all of the following are true:
- You are married.
- Your spouse is your sole primary beneficiary for the year.
- Your spouse is more than 10 years younger than you.
This table often produces a larger life expectancy factor, which can result in a smaller RMD.
Common planning implication: when it applies, it can reduce the required taxable distribution for that year and potentially help manage brackets, Medicare premium thresholds, or big one-time income years.
3) Single Life Table (often relevant for inherited accounts)
The Single Life Table is commonly used for certain inherited IRA situations.
Inherited account distribution rules can be complex, especially with changes in law and how beneficiaries are classified. The correct method can depend on several factors, including the beneficiary’s relationship to the original owner and when the owner passed away.
If you inherited an IRA, do not assume the custodian’s default table is correct without a second look.
Life changes that can change your table (and your RMD)
It is easy to think “we set my beneficiaries years ago” and move on. But life changes can quietly shift which table you should be using.
Re-check your RMD table if you have experienced:
- Marriage
- Divorce
- Death of a spouse
- A spouse becoming (or no longer being) your sole beneficiary
- A new beneficiary designation after a family change
Even when everything is emotionally and administratively “settled,” it is worth confirming the tax mechanics.
A simple RMD checklist (a quick pre-flight check)
Before you rely entirely on a custodian’s number, run through this short checklist.
Confirm the December 31 value is complete
Ask yourself:
- Did I do a rollover near year-end (money “in motion”)?
- Did I move funds between custodians in December or early January?
- Did I consolidate accounts or close an account late in the year?
Confirm there were no special adjustments
- Did I complete an IRA recharacterization?
- Did I buy or modify a QLAC (and could an excess amount exist)?
Confirm the right IRS table applies
- Am I using the Uniform Lifetime Table by default, and is that correct?
- If married, is my spouse my sole beneficiary and more than 10 years younger?
- Is this an inherited account with its own distribution method?
Confirm the “plumbing” details
- Am I taking the RMD from the right accounts?
- Am I withholding taxes appropriately from distributions?
- If I have multiple IRAs, do I understand aggregation rules and the limits of aggregation when employer plans are involved?
Those last points are worth a conversation because RMD rules can differ depending on account type.
Why it is worth getting this right: the hidden ripple effects of an RMD mistake
The obvious risk of an RMD error is a potential IRS penalty for failing to distribute the required amount on time.
But even when a shortfall is corrected later, RMD mistakes can have ripple effects.
- Tax return complexity: amendments or explanatory filings may be needed.
- Cash-flow surprises: a “catch-up” distribution can create an unexpected tax bill.
- Medicare premiums: a higher-income year can affect future Medicare premiums.
- Charitable plans: if you intended to use a qualified charitable distribution (QCD) strategy, timing matters.
The goal is not perfection for perfection’s sake. It is avoiding avoidable tax friction and keeping your retirement plan running smoothly.
Practical planning tips around RMD season
Even when the calculations are straightforward, the implementation matters.
Spread distributions out if it helps your cash flow
Some retirees take the full amount late in the year. Others take monthly or quarterly distributions to smooth budgeting and tax withholding.
Consider tax withholding intentionally
You may be able to withhold federal (and sometimes state) taxes directly from distributions. This can be a convenient way to cover tax obligations without making separate estimated payments, though the right approach depends on your broader tax picture.
Coordinate across accounts
If you have multiple retirement accounts, the “right” withdrawal strategy often involves more than RMD math. It can include:
- Which assets to sell (cash, bonds, equities)
- Whether you are rebalancing
- Whether you are coordinating with Social Security, pensions, or other income
Revisit beneficiaries every year, or after any change
Beneficiary designations are not “set it and forget it.” They are part of the RMD equation in certain cases, and they matter for estate planning as well.
Bringing it all together
At a high level, RMDs are a two-step process.
- Start with the correct December 31 value and confirm it is not missing money that was in transit or otherwise needs to be added back.
- Use the correct IRS life expectancy table (Uniform in most cases, Joint in one specific spouse-beneficiary scenario, and Single Life often for inherited account situations).
For many households, the custodian’s calculation will be correct. But if your year included a rollover around year-end, a recharacterization, or a QLAC issue, or if your family situation changed, the custodian’s number may be incomplete.
A helpful mindset is to treat your annual RMD review like a pilot’s pre-flight checklist. It does not take long, and it can spare you from bigger problems later.
If you would like, we can review your year-end statements, beneficiary designations, and any account movement during the year to help confirm your RMD numbers and coordinate the distribution with your broader tax and retirement-income strategy.