There's a number you've been thinking about — the sale price. Maybe it's a business you've spent decades building, or a commercial property that's appreciated well beyond what you ever imagined. You know the headline figure. What you probably don't know — not with any precision — is what you'll actually keep.
That gap between the gross number and your real, after-tax, year-by-year cash position is exactly where financial decisions go wrong. And it's where thoughtful planning creates the most value.
For many sellers, this is the first time they've faced a transaction of this magnitude without an institutional support structure behind them. If you ran a company, you had a CFO, a controller, or an in-house tax team helping you navigate complex financial decisions. When you sell — or when you leave a senior executive role — that infrastructure disappears. You're now managing the most consequential financial event of your life, often with less technical support than you had managing a quarterly close.
The answer isn't to worry about it. The answer is to model it.
Why Liquidity Events Are Different from Everything Else on Your Tax Return
Most of your financial life is relatively predictable on a year-by-year basis. Income comes in, taxes go out, and the picture is roughly consistent. A large sale event changes all of that — and the complexity isn't just about the amount. It's about the layers.
Consider what happens when a major sale closes in a single tax year. You may have federal long-term capital gains tax at up to 20%. On top of that, sellers may be subject to the 3.8% Net Investment Income Tax (NIIT) on investment gains. Add California or another high-income state's tax — California taxes capital gains as ordinary income, at rates up to 13.3% — and you're looking at a combined marginal rate that can approach or exceed 37% on each additional dollar of gain.
But here's what most sellers don't realize until it's too late: these layers don't apply uniformly to everyone, and some of them can be reduced with the right planning in advance.
The NIIT exception that active business owners often miss. The 3.8% NIIT was designed to tax passive investment income — not the gain from a business you've actively run. Under current tax law, if you materially participated in your business on a regular, continuous, and substantial basis, the gain from its sale may be entirely excluded from the NIIT calculation. For a business owner with a large gain, that 3.8% difference is meaningful money — and whether it applies depends on facts and structuring, not luck.
Real estate investors face a related but distinct analysis. Gain from the sale of rental or commercial property is generally subject to NIIT unless the taxpayer qualifies as a real estate professional and the activity is treated as an active trade or business. The characterization of your activity during the holding period determines the tax treatment at sale.
These distinctions matter enormously when you're modeling what you'll actually net.
The Planning Horizon: It's Not All or Nothing
If you've already signed a letter of intent, it doesn't mean you've missed your window — but the honest answer is that the most powerful planning tools are available to those who start early.
Think of it as a tiered timeline, where each phase offers a different set of levers:
Three or more years before the transaction: This is where the most consequential planning lives. Entity structure decisions, gifting of pre-appreciation interests to family members or trusts, installment sale eligibility analysis, QSBS (Qualified Small Business Stock) holding period planning, and charitable vehicle establishment. At this stage, you're doing true structural planning — not just tax mitigation.
One to two years before: Bracket modeling becomes central. You can begin mapping out the transaction year — projecting how the gain interacts with your other income, identifying whether there are income acceleration or deferral opportunities, and beginning to coordinate with estate planning counsel. This is also when you should be setting up any trust structures you intend to fund before the closing.
Six to twelve months out: The estate planning window is still open, but it's narrowing. Charitable strategies — a donor-advised fund, a charitable remainder trust, a direct gift — can still be structured. A preliminary multi-year cash flow model should be running at this point, even if the numbers are estimates.
At or after closing: More doors have closed, but not all of them. Estimated tax planning, investment of proceeds, Roth conversion sequencing, and continued estate planning work all remain available. The model doesn't stop being useful at the closing table — it becomes the foundation for everything that comes next.
The point isn't to make sellers feel behind if they haven't started years in advance. The point is that there is always something to model, and modeling is generally intended to support more informed decisions than acting without a structured analysis.
What Multi-Year Modeling Actually Looks Like
This is the core of what we do at Brickley Wealth Management, and it's where the real clarity comes from.
A multi-year tax and cash flow model for a major sale isn't a simple tax projection for the closing year. It's a year-by-year picture — typically covering the transaction year plus four or five years forward — that answers the questions that actually matter:
- What is your estimated federal and state tax liability in the transaction year, broken down by tax category?
- What are your estimated tax payments due and when — and how do you avoid underpayment penalties for an event of this size?
- What does your adjusted gross income look like in each of the following years, and how does that affect your tax planning options?
- What is the after-tax cash available from the sale, net of all tax obligations, and how does it flow into your investment portfolio over time?
- What opportunities does your post-liquidity income profile create — and when?
That last question is the one that surprises sellers most. A large liquidity event often produces several years of unusually low ordinary income afterward — particularly if the seller was drawing a salary from the business they just sold. Those lower-income years aren't a problem. They're an opportunity, and a well-built model identifies exactly how to use them.
The Three Levers That Move the Needle Most
1. Income Tax Timing and Bracket Management
The transaction year is almost always a high-income year. The goal isn't to eliminate that — you can't compress decades of appreciation into a zero-tax event. The goal is to understand the tax stack precisely and make deliberate decisions about everything around it.
This includes: whether any gain can be recognized across two tax years (installment sale), whether there are capital losses elsewhere in the portfolio that can be harvested, how depreciation recapture is categorized and taxed for real property sales (Section 1250 recapture is taxed at a maximum 25% federal rate, not the standard long-term capital gains rate), and how the NIIT analysis plays out given your specific participation history.
For business sellers, purchase price allocation also matters significantly. How the sale price is divided among different asset classes — goodwill, equipment, non-competes, inventory — directly affects the mix of ordinary income versus capital gain, which affects both your top marginal rate and your NIIT exposure. This negotiation happens before closing, not after.
2. Cash Flow Sequencing: What You Net and When
The gross sale price isn't the only variable. So is the timing of when you actually receive the cash, and when your tax obligations come due.
An installment sale, for example, spreads gain recognition across multiple years — which can keep you in a lower bracket in each individual year, reduce overall NIIT exposure, and create a more predictable income stream. The tradeoff is deferred receipt of proceeds and continued exposure to the buyer's credit risk. Whether it makes sense depends on your specific income profile and the buyer's financial strength — exactly the kind of analysis a model surfaces quickly.
Estimated tax payments are another area where sellers consistently underestimate the complexity. A large gain in Q1 or Q2 of a tax year creates estimated payment obligations for that same year, and the penalty calculations are not always intuitive. A well-built cash flow model maps payment due dates, amounts, and the interplay between federal and state estimated payments — so you're not surprised by a cash demand you didn't plan for.
3. Estate and Gift Tax Integration
For sellers whose estates may approach or exceed the federal lifetime exemption — $15 million per individual in 2026 under provisions of the One Big Beautiful Bill Act signed in July 2025, up from $13.99 million in 2025 (though tax law is always subject to future legislative change) — the period around a major liquidity event is often the most important window for estate planning action.
The reason is straightforward: when you gift an asset before it appreciates, you're removing a smaller value from your taxable estate. A business interest or property gifted before a transaction that closes at a higher value removes far more future wealth from the estate than a gift of the same asset made after closing when its value has been realized. Every year of inaction on this front is an implicit decision to expose more of your estate to a potential 40% tax rate.
Common planning vehicles in this context include irrevocable trusts (SLATs, dynasty trusts, GRATs), outright gifts to family members using the annual exclusion ($19,000 per recipient in 2025/2026), and charitable vehicles. The right structure depends heavily on your family situation, state law, and the nature of the asset — which is why this planning requires close coordination between your CPA, your financial advisor, and your estate attorney.
Even sellers who are confident they're well below the estate tax threshold benefit from this analysis. The model clarifies your projected estate size post-liquidity, which is often larger than sellers initially expect once the after-tax proceeds are invested and begin compounding.
The Post-Liquidity Roth Conversion Window
One of the more counterintuitive planning opportunities that a multi-year model consistently identifies is the Roth conversion window that often opens in the years immediately following a major sale.
Here's the logic: the transaction year itself is typically not the time for Roth conversions — income is already at its peak. But in years two, three, and four post-closing, ordinary income may normalize or even decline significantly, particularly if the seller is no longer drawing a salary. That creates a window where meaningful IRA balances can be converted to Roth at lower marginal rates than may ever be available again.
For a seller who has accumulated a substantial IRA or 401(k) balance over a career, this window may present meaningful Roth conversion planning opportunities — the value of which depends on individual tax circumstances, account balances, and future tax rates, which are uncertain.
The Team Behind the Model
A multi-year tax and cash flow model of this complexity isn't something you pull together over a weekend. It requires close coordination across disciplines: a CPA who understands both the transaction tax treatment and the ongoing tax picture, a financial advisor who can model the post-liquidity investment and income scenarios, and an estate attorney who can execute on the planning recommendations before the window closes.
The coordination problem is real. Too often, sellers work with professionals who are excellent within their own domain but aren't regularly talking to each other. The CPA handles the return. The attorney drafts the trust. The financial advisor manages the investments. Nobody owns the integrated picture — and the gaps are where planning value gets left behind.
At Brickley Wealth Management, Steve Brickley, CPA, brings more than 40 years of experience in tax matters related to major liquidity events, including business sales and real estate transactions. That work is fully integrated with our wealth management and financial planning team, so the model we build for you isn't a one-time projection. It's a living tool that evolves as the transaction takes shape and continues to guide decisions in the years that follow.
If you're approaching a significant exit — or you're already working through one — and you'd like to see what a multi-year model of your specific situation might reveal, we'd be glad to start that conversation.