Most people learn about required minimum distributions the way you learn about a pothole: by hitting it. A letter arrives from the custodian, there's a number on it, and the number is bigger than expected.
The deadline part is simple. The planning part is where the money is — and by the time the letter shows up, most of the good moves are behind you.
The mechanics, in about sixty seconds
If you were born between 1951 and 1959, your required minimum distributions start at age 73. If you were born in 1960 or later, they start at 75 under SECURE 2.0.
The calculation is one division problem. Take your December 31 balance from the prior year and divide it by the distribution period for your age in the IRS Uniform Lifetime Table. At 73, that divisor is 26.5. At 74 it's 25.5. At 75 it's 24.6.
So a $1.4 million traditional IRA produces a first RMD of about $52,830 ($1,400,000 ÷ 26.5). That's roughly 3.8% of the balance.
One wrinkle worth knowing: your first RMD can be delayed to April 1 of the following year. That sounds like a gift. It usually isn't. Delaying stacks two distributions into the same calendar year — the delayed one plus the one due that December 31 — which can push you into a higher bracket, tax more of your Social Security, and raise your Medicare premiums two years later. Most people are better off taking the first one on time.
Also worth knowing: Roth IRAs have no lifetime RMDs for the original owner, and since 2024, neither do Roth 401(k) and Roth 403(b) accounts. That fact does a lot of quiet work in the planning section below.
Why the divisor gets worse every year
Here's the part people miss. The RMD isn't a flat percentage. The divisor shrinks as you age, so the required percentage of your balance climbs — and if your portfolio is still growing, the dollar amount climbs faster than the percentage.
Take that same $1.4 million IRA, assume 5% growth, and take exactly the minimum each year:
| Age | Divisor | RMD |
|---|---|---|
| 73 | 26.5 | $52,830 |
| 75 | 24.6 | $58,009 |
| 78 | 22.0 | $65,983 |
| 80 | 20.2 | $72,044 |
You take out over half a million dollars across those years and the balance barely moves. Meanwhile the forced income has grown by about 36%. Nobody sends you a warning about that in your sixties, which is exactly when you could still do something about it.
What the RMD actually touches
An RMD is ordinary income. That single line item ripples outward in at least three directions.
Your bracket. For 2026, the 22% bracket for married couples filing jointly starts at $100,800 of taxable income and the 24% bracket starts at $211,400. The standard deduction is $32,200, plus an additional $1,650 per spouse age 65 or older. There's also a temporary senior deduction: for tax years 2025 through 2028, taxpayers 65 or older may claim an additional $6,000 per person, phasing out above $75,000 of modified AGI for singles and $150,000 for joint filers. A large RMD can quietly phase that deduction away.
Your Social Security. Up to 85% of benefits become taxable depending on "provisional income." The thresholds are $32,000 and $44,000 for joint filers, $25,000 and $34,000 for singles — and critically, those numbers are not indexed for inflation. They haven't moved in decades. An RMD is one of the fastest ways to drag more of your benefit into the taxable column.
Your Medicare premiums. The standard Part B premium in 2026 is $202.90 a month. Above a modified AGI of $109,000 (single) or $218,000 (joint), the income-related monthly adjustment amount kicks in and the total Part B premium climbs to $284.10 at the first tier. IRMAA uses a two-year lookback, so 2026 premiums are based on your 2024 return. That lag is why the planning has to happen early: the bill for this year's income shows up two years from now.
Worked example. A couple, both 80, drawing $60,000 in Social Security, $20,000 in dividends and interest, and a $72,044 RMD. Roughly $51,000 of their Social Security becomes taxable, AGI lands near $143,000, and federal tax runs about $11,000. Had earlier planning shrunk that IRA enough to cut the RMD to $45,000, the bill drops to roughly $7,500 — about $3,400 a year, repeating annually, from one decision made fifteen years earlier.
Four levers, roughly in order of usefulness
1. Convert before 73, not after. The window between retiring and your RMD start date is usually the lowest-income stretch of your adult life. Wages have stopped, Social Security may not have started, and RMDs haven't begun. Converting traditional dollars to Roth in that window shrinks the balance that future RMDs are calculated from — permanently. Every dollar converted at 12% is a dollar that never gets forced out at 22% or 24%. This is the single highest-leverage move available, and it expires the moment RMDs begin.
2. Qualified charitable distributions. From age 70½, you can send money directly from an IRA to a qualified charity and exclude it from income. For 2026 the limit is $111,000 per person ($222,000 for a couple, each from their own IRA). QCDs can satisfy your RMD. The key difference from writing a check: a QCD keeps the money out of AGI entirely, which means it doesn't inflate the Social Security calculation and doesn't count toward IRMAA. A charitable deduction can't do that. If you give anyway, this is close to free money.
3. Withdraw more than the minimum in cheap years. The RMD is a floor, not a ceiling. If a year leaves room at the top of the 12% bracket, filling that room deliberately is often better than protecting the deferral and getting taxed harder later.
4. Take it on time. Missing an RMD triggers an excise tax on the shortfall. SECURE 2.0 reduced it from the old 50%, and it drops further if you correct the miss promptly, but it's still an unforced error. Set the distribution to happen automatically.
The real problem is that this isn't a one-year question
Every lever above requires comparing a tax bill you'd pay now against a stream of tax bills stretching decades out — including how the RMD interacts with your Social Security claiming age, your Medicare premiums two years later, your state's treatment of retirement income, and what happens to the survivor when a joint filer becomes a single filer at half the bracket width.
That's not a spreadsheet question. It's a projection question. Tally models your accounts, taxes in all 50 states, and the full withdrawal sequence to the end of your plan, so you can see what a conversion at 66 does to your RMD at 80 — and to the tax you'd owe on it — before you commit.
The first RMD is the deadline. The plan should have started a decade earlier.
Tally isn't a tax advisor. Figures here are 2026 amounts from the IRS and CMS. Run your own situation before acting.