Get in Touch
985 South Lamar Street, Dallas, TX 75202, United States
Thinking about selling or transitioning?
Share your situation and we'll discuss how we work. No fees, no pressure, one initial call.
Start the conversation
Usually yes, the closing date is worth planning, because when you sell your business decides which tax year, Medicare premium year and contribution limits the gain hits, and Corient Wealth Management maps all three first. Rule of thumb: a January closing moves the balance due on the gain from about 4 months after closing to about 15 months. A closing in the calendar year you turn age 63 or later shows up in your Medicare premiums 2 years later.
This decision rarely begins in a boardroom. It shows up when a buyer emails a draft letter of intent that names an arbitrary target closing date, such as December 20, or when an owner wonders whether holding out for another year changes anything beyond fatigue. Moving the closing by just 3 weeks can push a tax bill of hundreds of thousands of dollars from one IRS calendar year into the next, and that decides exactly when your cash must leave your custody.
Founders ask Corient Wealth Management these questions in early conversations, usually with the draft letter of intent already open. We start with the tax bill. We weigh the federal payment deadlines on the gain, the 401(k) deferrals still possible through final payroll, and the Medicare premium year the gain will land in, then we weigh all of that against the risk that the deal goes stale.
Closing in January pushes the tax off a whole year
Owners often say a January closing saves a year of tax. The rule is that the gain is taxed in the year the sale closes. The overall rate is generally the same either way. What actually moves is the date the final balance must be sent to the government.
That payment postponement relies on the IRS estimated-tax safe harbor. If your adjusted gross income on the prior year's tax return exceeded $150,000, paying 110% of that prior year's total tax across 4 equal quarterly installments shields you from underpayment penalties, even if your income multiplies tenfold in the current year. The true tax cost on the windfall sits in your accounts until April 15 of the following spring.
A hypothetical couple, Boyd (age 61) and Tracy (age 59), receive a draft letter of intent naming a December 20 closing for their S corporation landscaping supply company on a $6,000,000 sale. For illustration, assume a $1,000,000 federal tax cost on the gain and $120,000 of ordinary tax in a typical year. If they close on December 20, the $1,000,000 balance is due on April 15, about 4 months later. If they shift the agreement to January 5, their quarterly estimates for that entire sale year only need to equal 110% of $120,000, which is $132,000 total, or $33,000 each quarter. The remaining balance on the transaction is not due until April 15 of the following year, roughly 15 months after closing.
Holding that $1,000,000 balance for an additional 11 months, assuming 4% a year for illustration, generates about $36,700 in interest ($1,000,000 multiplied by 4% multiplied by 11 divided by 12). Boyd turns age 62 during that January, so Medicare premiums remain completely unaffected 2 years later.
Before Corient Wealth Management suggests asking a buyer for a later date, our team compares that interest with the risk of the deal slipping. A few weeks of delay can put price and terms back on the table, so the move is a tax trade-off, not a free gain. The arithmetic here covers federal guidelines only; state estimated-tax rules differ, so check your state's rules.
| Date | What is due | What it means for a sale |
|---|---|---|
| January 15 | 4th-quarter estimated tax | Safe-harbor payment, not the gain |
| April 15 | Return and balance due | Tax on last year's closing due |
| June 15 | 2nd-quarter estimate | $33,000 safe-harbor installment in example |
| September 15 | 3rd-quarter estimate | Same $33,000 installment |
| Final payroll before closing | Last 401(k) deferral | Up to $35,750 at age 61 |
| December 31 | Last day to close this year | Gain enters this year's MAGI |
We'll sell once we're both on Medicare and life is quieter
Medicare Part B premiums for any calendar year are calculated directly from your modified adjusted gross income 2 years earlier. A capital gain recognized in the calendar year you turn age 63 or later lands squarely inside a lookback period when you are enrolled in Medicare. For 2026, the highest income tier imposes a $689.90 monthly premium per person, compared to the $202.90 standard premium, whenever joint income reaches $750,000 or above.
A relative advising an owner to delay the exit until normal retirement can easily trigger an unnecessary surcharge. Tracy's brother urged the couple to wait until Boyd turned age 66 to close, arguing that exiting when the paychecks stopped made life simpler. Closing in that year, when Boyd was age 66 and Tracy was age 64, placed the multi-million-dollar transaction into the lookback period for the year Boyd turned age 68 and Tracy turned age 66, when both were enrolled in Medicare. The extra cost is $11,688 for that single year (($689.90 minus $202.90) multiplied by 12 months multiplied by 2 people), plus an additional Part D monthly surcharge (check the current amount). To catch this trap, write down your target closing year, add 2, and identify who will be enrolled in Part B during that future year.
A separate procedural slip occurs when an owner closes in December and forgets the January 15 fourth-quarter estimate. Failing to submit that safe-harbor payment incurs an IRS underpayment penalty, assessed like interest, on the amount that fell short.
The retirement plan can wait until after the sale
Employee 401(k) deferrals must come out of active W-2 payroll before your final paycheck processes, because in an S corporation, shareholder distributions do not qualify as compensation. Using 2026 limits, an owner like Boyd at age 61 can defer up to $32,500, which includes the standard $24,500 limit plus the $8,000 catch-up permitted for ages 50 to 59. A spouse on payroll, such as Tracy at age 59, can contribute up to $32,500, combining the $24,500 limit and the $8,000 standard catch-up. Catch-up contributions must be designated as Roth if prior-year FICA wages exceeded $150,000. A December 20 closing allows a full 12 months of wages to fund those accounts, whereas closing on January 5 leaves only days of payroll, eliminating retirement deferrals for that new year unless an operating entity remains active.
When to sell your business if you don't fit the usual timing
If you are already age 63 or older, every potential closing year hits a Medicare premium year 2 years later. Shifting between December and January merely decides which calendar year carries the surcharge, not whether you avoid it. The IRMAA bracket spike lasts only 12 months, returning to baseline once your income normalizes, provided subsequent portfolio gains stay moderate.
If you are already age 63 or older, every potential closing year hits a Medicare premium year 2 years later. Shifting between December and January merely decides which calendar year carries the surcharge, not whether you avoid it. The IRMAA bracket spike lasts only 12 months, returning to baseline once your income normalizes, provided subsequent portfolio gains stay moderate.
Alternative deal structures change the calendar math entirely. Payments structured through a promissory note spread income across future periods under installment treatment, while earn-outs are taxed strictly as cash arrives. Relocating your personal residency to another state before executing agreements can alter state-level obligations, so check your state's rules.
Which dates Corient Wealth Management compares before the letter of intent
Before transaction terms are set, Corient Wealth Management compares three closing dates on four points: when the tax is paid, the Medicare effect, the 401(k) room left and the deal risk. All three assume a joint return, standard safe harbors and steady asset values. A December 20 closing means the full federal balance is due in roughly 4 months. It adds no Medicare surcharge at Boyd's age 61, it leaves a full year of 401(k) wages, and the deal risk is low. A January 5 closing moves the balance out to roughly 15 months. It also adds no Medicare surcharge, leaves almost no payroll for new deferrals and carries a small execution risk. Waiting until Boyd is 66 does not lower the tax. The balance is still due the April after that later closing, and the sale year adds $11,688 in Part B surcharges for one year. It does buy several more years of retirement deferrals, at the highest risk that buyer appetite or valuations soften.
When timing your transaction, follow these concrete steps in exact sequence:
Collaborative execution makes this sequence work. The wealth advisor models the calendar milestones, the CPA calculates quarterly safe-harbor payments, and the transaction attorney drafts the closing window into the purchase agreement.
- Pull last year's federal tax return
- Calculate 110% of total tax liability
- Negotiate a flexible closing window
- Instruct your CPA on quarterly payments
- Execute final employee retirement deferrals
- Isolate tax reserves upon wire receipt
What question should you bring if your closing date is still open?
Given our target closing window and our ages, which tax year and which Medicare premium year will this transaction hit? Ask Corient Wealth Management how each possible closing date changes the dollar amount you owe, when you must write the check, and how many retirement contributions you can still complete. Bring your draft letter of intent and your prior year's tax return so the calculations reflect your exact numbers.
Questions about when to sell my business
Should my parents wait until Dad is on Medicare before selling the business?
Usually no. Medicare premiums are set by income from 2 years earlier, so a sale closed in the year a spouse turns 63 or later will count toward a year when that spouse is on Medicare. A large enough gain, $750,000 or more of joint MAGI for 2026, puts both enrolled spouses in the top IRMAA tier. A sale closed while both spouses are 62 or younger falls into lookback years before either is enrolled, so the gain never raises their Part B or Part D premiums.
By what date is the tax on a January closing actually due?
For a transaction closing in January, the full remaining balance of federal tax is due on April 15 of the following calendar year, approximately 15 months later. However, you must maintain four quarterly safe-harbor estimated tax payments throughout that sale year, typically totaling 110% of your prior year's tax liability, to avoid IRS underpayment penalties.
How much more does Medicare cost after a large sale-year gain?
For 2026, reaching the top modified adjusted gross income threshold of $750,000 or more on a joint return raises the Part B premium from $202.90 to $689.90 a month per individual. For a married couple both enrolled in Medicare, that single-year increase equals $11,688 in added Part B costs, plus extra monthly Part D surcharges.
Can we write a target closing month into the letter of intent?
Yes, buyers and sellers routinely specify a target closing month or an outside closing date in the letter of intent. Defining this timeline early protects the transaction schedule and gives your legal and advisory team the operational runway needed to align the sale with your chosen tax year and quarterly safe-harbor payment dates.
Does the wire date or the closing date decide the tax year of the sale?
The legal closing date specified in the definitive purchase agreement governs when the sale occurs for federal income tax purposes, provided the benefits and burdens of ownership transferred then. If a transaction legally closes on December 31, the gain belongs in that tax year, even if funds wire on the first banking day of January.
Is a mid-year closing ever better than December or January?
A mid-year closing can be advantageous if your operating business experiences heavy, predictable seasonal revenue during the fall that you wish to exclude from your personal tax return. Closing mid-year also provides sufficient remaining calendar months to fully fund executive 401(k) accounts or implement cash balance retirement contributions from pre-closing W-2 wages.
Quick summary
- Check your age against the two-year Medicare lookback before agreeing to push a closing date past age 62.
- Calculate 110% of your prior year's tax liability to utilize the federal estimated-tax safe harbor.
- Max out active W-2 payroll deferrals to your 401(k) before executing final company sale documents.
- Separate the April 15 tax balance into a dedicated interest-bearing account the day closing funds wire.
Primary sources
This content is general information for educational purposes. It is not individualized investment, tax or legal advice for your situation. Investing involves risk, including the possible loss of principal. Before making financial decisions, consult a qualified professional who understands your circumstances.