What One Big Sale Year Really Costs You (Beyond the Tax Bill)
A large gain does more than raise your capital gains tax. For the year of the sale (and, for Medicare, two years later), it can raise your Medicare premiums, shrink your SALT deduction, switch on AMT and the 3.8% NIIT, make more Social Security taxable, erase an ACA premium credit and phase out the senior deduction. Each cost switches on at a specific 2026 income line, so plan against the lines, not only the tax rate.
The costs below show up later, on a Medicare notice or a smaller refund. This page is the checklist and the hub: each line links to a deeper article, and the calculator now has a "Beyond the tax bill" slide that prices them for your numbers.
Which income lines does a sale year cross in 2026?
What is the tax bill on your sale going to be?
Send me the sale price and rough basis. Within one business day I'll email you the actual number and the Seller's Guide to §453. If it doesn't fit your deal, I'll tell you that plainly.
No retainer · no obligation. Hans Goldstein, a licensed insurance agent (CA Insurance License #4273294), will contact you and may discuss insurance products, including annuities.
What does each cost look like up close?
AMT on a property sale. The 2025 law pulled the AMT exemption phase-out start down to $1,000,000 joint ($500,000 single) and doubled the phase-out rate to 50%. A big gain wipes out the exemption, so your ordinary income is suddenly taxed under AMT rates. For a Texas couple with $200,000 of ordinary income and a $2M gain, the engine shows $25,660 of AMT in 2026.
The SALT cap and your sale year. The cap rose to $40,400 for 2026, but it shrinks by 30 cents per dollar of MAGI over $505,000 and bottoms out at $10,000. A California couple with $605,000 of AGI keeps a cap of only $10,400 and pays about $6,600 more federal tax. At very high income, AMT absorbs most of that loss.
IRMAA after a property sale. Medicare looks back two years, so a 2026 sale sets your 2028 Part B and Part D premiums. A voluntary sale is not a life-changing event you can appeal (20 CFR 418.1205; POMS HI 01120.005). The top 2026 tier costs $6,936 a year per person in surcharges alone. See also capital gains and IRMAA on our calculator site.
Social Security taxes after a sale. The §86 lines ($32,000 and $44,000 joint) are not indexed for inflation, so almost any gain pushes benefits to the 85% maximum. For a Texas couple with $48,000 of benefits and a $700,000 sale, the extra tax on benefits over 10 years runs from about $36,500 (cash) to $54,200 (10-year spread).
The ACA subsidy cliff. The enhanced credits expired after 2025 and the House-passed extension (H.R. 1834) was never enacted. A couple under 65 at $84,600 of household income gets a $17,574 credit on a $26,000 benchmark plan; at $84,601 they get nothing.
Roth conversions and an installment sale. In the engine example, a $100,000 conversion costs $23,631 in federal tax, NIIT and IRMAA in a quiet year, $33,148 on top of a $150,000 installment-gain year and $36,585 on top of a $1.5M cash-sale year. Conversion room is income room, and the sale uses it first.
California's top brackets and 2031. Prop 55's 10.3/11.3/12.3% brackets apply to tax years before 2031. For a $12M joint sale spread over 10 years, California tax on the 2031 to 2035 payments is $618,439 at today's rates and $567,635 if the brackets expire. Prop 3 on the November 3, 2026 ballot would make them permanent.
Two more lines belong on the list. The senior deduction of up to $6,000 per person disappears at $175,000 single or $250,000 joint MAGI. And the 3.8% net investment income tax applies to the gain above $200,000 or $250,000, with no inflation adjustment.
What did the engine show for two real-size sales?
Both cases were run through the same 2026 engine that powers the calculator and checked live on the page. "Cash" means all gain in 2026. "Spread" means a structured installment sale with level payments at a 5% payout rate. Both sides earn the same 5% on money at work, and that income counts every year. Beyond-the-bill costs are measured against the same household with no sale.
Case 1: $6.5M sale, married, California, both 66
Basis $1.5M, selling costs $357,500, $150,000 other income, $60,000 Social Security, $25,000 property tax, $10,000 charity, 10-year spread, two people on Medicare.
Why the spread pays more IRMAA: its yearly income ran about $873,000 to $1.07M, the top tier every year. Why the cash side still pays a lot: its invested proceeds kept MAGI between about $431,000 and $498,000, tier 4 every year after the sale. On SALT, AMT absorbed the lost deduction in the cash year, while the spread lost about $2,200 to $3,300 a year through 2029 before the cap drops to a flat $10,000 for everyone.
Case 2: $1.5M sale, single, California, age 66
Basis $400,000, selling costs $82,500, $40,000 other income, $30,000 Social Security, $8,000 property tax, $2,000 charity. Run it yourself.
The cash seller pays the top IRMAA tier once ($6,936), then mostly tier 1. The 10-year spread seller sits at $217,000 to $269,000 of income, tier 4 ($6,355 a year) for all 10 years.
What is the honest conclusion?
Spreading the gain cut the tax bill by far more than it added in IRMAA and SALT: $347,176 against $22,195 in Case 1, and $129,313 against $42,711 in Case 2.
But in both cases the beyond-the-bill costs were higher on the spread, not lower. The reason is simple: a spread keeps income above the lines for years instead of crossing them once. Spreading does not automatically dodge IRMAA or the SALT phase-down. It changes one big crossing into many smaller ones.
Two points follow:
- The fix is design, not duration. Size each year's payment against the specific line: the IRMAA tier edge ($109,000 single, $218,000 joint, then each higher step), the $505,000 SALT threshold, 400% of poverty if you buy marketplace coverage, the §86 lines if you collect Social Security. A few thousand dollars of income can decide a whole tier.
- A cash seller's money earns income too. Case 1's cash seller never got back under IRMAA, because the after-tax proceeds, invested at 5%, are income every year. Comparing a spread against a cash sale that "only hurts once" overstates the cash side.
Where does a structured installment sale fit?
It is one way to control which year the gain lands in. The buyer pays in full at closing, and you take the proceeds as scheduled payments from an assignment company, funded by an annuity from a highly rated life insurer. What to know: the payments are locked in once set, they depend on the assignment company and the insurer behind it, there is no published IRS ruling on this specific assignment structure (so have your CPA review it), and a commission is built into the pricing. See what a structured installment sale is and IRC §453.
Frequently asked
Q: Does spreading a sale always lower Medicare premiums? A: No. In both engine cases the spread paid more IRMAA over time, because income stayed above a tier for years. It lowers IRMAA only when each year's income is sized under a tier edge.
Q: Can I appeal IRMAA after selling property? A: Not for the sale itself. A voluntary sale and a one-time capital gain are listed as non-qualifying events in POMS HI 01120.005. Stopping work or a spouse's death can qualify.
Q: Does the gain count against my ACA credit? A: Yes. It is in the MAGI used for the premium tax credit, and above 400% of poverty the credit is zero for 2026.
Q: Where can I price these for my own sale? A: The calculator has a "Beyond the tax bill" slide with inputs for Medicare, Social Security, property tax, mortgage interest, charity and ACA coverage. The capital gains exit calculator covers the headline tax.
What should you read or run next?
- Structured installment sales for high earners
- Capital gains tax by state
- Calculator with the "Beyond the tax bill" slide
- Capital gains exit calculator
Illustrative estimates using 2026 law. Not tax, legal or accounting advice. Figures change each year; have your CPA confirm with your own return.
Who wrote this?
Find out what your sale is really going to cost you in tax, and what you can do about it
No retainer. On a funded structure, the insurer pays a one-time commission of about 4% of the amount structured to the brokerage firm that places it (Hans’s share is about 2.4%; no trail). It is built into the annuity pricing, not a separate fee.
Find out what your tax bill actually looks like before you sell, including the parts your CPA may not raise until the return is already being prepared.
Most people find out what they owe after the sale closes, when nothing can be changed. A short conversation now tells you the number, which layers apply to your situation, and which options are still open while the sale is still in front of you.
- What you will actually owe: federal, the 3.8% surtax, recapture and your state
- Which of those layers you can still do something about
- Whether spreading the sale changes the number in your case
Hans Goldstein · 213-340-2018 · Hans Goldstein: Tax & Exit Planning · This is an educational conversation, not tax advice. Bring your CPA in before you file.
Hans Goldstein, a licensed insurance agent (CA Insurance License #4273294), will contact you and may discuss insurance products, including annuities.
Run your specific numbers
The calculator runs your sale through real 2026 federal + state tax brackets and shows §453 savings vs lump sum side-by-side.
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