Buy-Sell Agreements: The Business Owner's Estate Planning Blind Spot

Most closely held businesses have a will, a trust, and life insurance for the owners' families — and no plan at all for what happens to the business itself when an owner dies, becomes disabled, or walks away. A buy-sell agreement fixes that. It's a contract among co-owners that answers three questions in advance: who buys the departing owner's interest, at what price, and how it gets paid for. Skip it, and the surviving owners can end up in business with a deceased partner's spouse — or in court with them. Here's how buy-sells actually work.

What a Buy-Sell Agreement Actually Does

A buy-sell agreement is a binding contract between the owners of a closely held business. It sits alongside — but is distinct from — the operating agreement, shareholders' agreement, or partnership agreement. Its job is to specify what happens to an owner's interest when a triggering event occurs.

The five triggering events that appear in nearly every buy-sell are:

• Death. The most common trigger, and the one that most directly overlaps with estate planning.
• Disability. Defined by a period of continuous inability to perform the owner's duties — often 6 to 12 months.
• Retirement or voluntary exit. Including a mandatory retirement age if the owners agree to one.
• Divorce. To prevent an ex-spouse from becoming a co-owner if the interest is deemed marital property.
• Involuntary transfer. Bankruptcy, judgment creditors, or expulsion for cause.

When a trigger fires, the agreement kicks in automatically. It identifies who has the right (or obligation) to buy, sets the price using a pre-agreed methodology, and specifies the payment terms. Without one, the departing owner's interest passes according to their will or state intestacy law — meaning the surviving co-owners may suddenly be doing business with a spouse, adult children, or an estate executor who never signed up for it.

The business succession guide covers the broader landscape of ownership transitions. This article zooms in on the contract at the center of it all.

The Three Main Structures

Buy-sell agreements come in three basic flavors. The choice among them has real tax and cash-flow consequences.

Cross-Purchase Agreements

In a cross-purchase, the remaining owners individually buy the departing owner's interest. If you and two partners each own a third of a business and one dies, you and the other surviving partner each buy half of the deceased partner's interest, ending up as 50/50 owners.

The main advantage is a stepped-up basis for the surviving owners — they've personally purchased the departed owner's interest, so their basis increases accordingly, which can meaningfully reduce capital gains tax if they later sell the business. The disadvantage is administrative complexity: with three owners, each owner needs a life insurance policy on each other owner, meaning six policies total. With four owners, twelve policies. It gets unwieldy fast.

Entity Redemption (Stock Redemption)

In an entity redemption, the business itself buys back the departing owner's interest. The company holds the life insurance policies, pays the premiums, and uses the death benefit to redeem the shares.

This is much simpler administratively — one policy per owner, held by the business, regardless of how many owners there are. It's the most common structure for businesses with more than two or three owners. The trade-off: no basis step-up for the surviving owners, and premiums paid by a C corporation on lives of owners may trigger accumulated earnings tax or (in some structures) alternative minimum tax issues.

Hybrid / Wait-and-See

A hybrid agreement combines both structures — typically giving the surviving owners the first right to purchase individually, with the entity obligated to redeem any interest the surviving owners don't buy. A pure "wait-and-see" structure leaves the choice open until the trigger occurs, letting the parties pick the more tax-efficient path at the time.

Hybrids maximize flexibility at the cost of complexity in the drafting. They're common in professional practices and larger closely held businesses where the right structure depends on facts that can't be predicted in advance.

Pricing the Interest: The Valuation Question

Every buy-sell has to answer the same question: at what price? Get this wrong and either the departing owner (or their family) is shortchanged, or the surviving owners overpay, or — worst case — the whole agreement is treated as a device to transfer wealth and gets ignored by the IRS at death.

There are four common approaches, sometimes used in combination:

1. Fixed price, updated annually The owners agree on a price, usually at the annual meeting, and update it in a signed schedule. Simple and cheap — until the price hasn't been updated in five years, the business has doubled, and the departing owner's family gets shortchanged. Only workable if there's real discipline about updating.
2. Formula-based A pre-agreed formula, most commonly a multiple of trailing earnings (EBITDA, net income, or revenue). Auto-updates as the business grows, but formulas that made sense at signing can become wildly wrong as the industry, capital structure, or business mix changes.
3. Independent appraisal at the trigger The agreement requires a qualified business appraiser to value the interest when the trigger fires, using specified methodology (fair market value with or without minority and marketability discounts). Most accurate, most expensive, and takes time — the surviving owners may need bridge financing to pay while the appraisal is completed.
4. Hybrid — formula with appraisal backstop Use a formula for speed, with the right for either party to demand an appraisal if the formula produces a result outside a specified band. This is the structure most estate planning attorneys recommend for businesses of any real size.

Funding: How the Purchase Actually Gets Paid

An unfunded buy-sell is a promise with no way to keep it. When the trigger fires, the buyer needs cash — often a lot of it — on short notice. There are four main funding sources.

Life insurance. The workhorse of buy-sell funding. Term life is cheapest and works well when the buy-sell is expected to fire in a defined window (say, before a planned retirement); permanent life insurance keeps up with owners who may hold their interest for decades. Either way, the death benefit provides immediate, tax-free liquidity to complete the purchase at exactly the moment it's needed. Our life insurance guide walks through policy selection in more detail.

Disability buyout insurance. A separate policy that pays a lump sum (or scheduled installments) if an owner becomes permanently disabled. Almost no one has this, and almost every buy-sell should. Disability is more likely than death for owners under 60, and the buy-sell trigger fires just the same.

Installment notes. The buyer purchases with a down payment and pays the balance over 5–10 years, secured by the interest itself. Cheap, but exposes the seller (or the family) to the ongoing credit risk of the buyer and the business.

Sinking fund or outside financing. Some businesses accumulate cash reserves earmarked for buy-sell purchases; others plan to borrow at the trigger. Both are workable but risky — the reserve may not have grown large enough, and outside lenders may not extend credit at the moment of a founder's death.

Common Mistakes We See Over and Over

Even businesses that have a buy-sell often have one that doesn't work when it needs to. The recurring failure modes:

1. No coordination with the estate plan The buy-sell says the interest passes to the surviving owners, but the departing owner's revocable trust says it passes to their spouse. When the two conflict, the buy-sell usually wins — but litigation over which document controls can freeze the business for months.
2. Stale valuation The fixed price was set in 2011 and never updated. The business has 5x'd. The departing owner's family gets shortchanged, or (if the valuation doesn't meet Section 2703) the family gets shortchanged and pays estate tax on the higher fair market value.
3. Underfunded or unfunded The agreement obligates a purchase the surviving owners cannot afford. The result is usually an installment note the family can't collect on if the business struggles, or a forced sale of the business itself.
4. Wrong policy owner In a cross-purchase, if the business owns the policies instead of the individual owners (or vice versa in an entity redemption), the tax treatment can go sideways — including the transfer-for-value rule that can turn tax-free death benefit into ordinary income.
5. No disability trigger Death is covered; long-term disability is not. When a partner has a stroke and can't return, the business has no mechanism to buy them out, no funding, and no exit for either side.
6. Never reviewed Ownership changes, spouses are added, the business restructures from an S corp to an LLC — and the buy-sell still references the original owners and the original entity. A buy-sell should be reviewed every 2–3 years and after every major life or business event.

When Should You Have One in Place?

If you own a business with anyone else — a co-founder, a family member, a longtime employee who's earned equity — you should have a buy-sell agreement. Full stop. It's not a document you draft when things go wrong; it's a document that keeps things from going wrong.

For sole proprietors and single-member LLCs, the equivalent is a written succession plan: who takes over, how the business is valued, who has authority in the interim, and how the transition is funded. Some of this can live in the operating agreement or a trust; some of it belongs in a standalone document.

The best time to sign a buy-sell is when everyone is healthy, the business is doing well, and no one has a reason to want a specific outcome. The worst time is after someone gets a diagnosis. Waiting until the second is how families and partners end up in court.

The Bottom Line

A buy-sell agreement is the connective tissue between a business owner's succession plan and their estate plan. Without one, the business becomes a liability inside the estate — hard to value, hard to sell, and hard to divide among heirs who may not want to run it. With a properly drafted, properly funded, and periodically reviewed buy-sell, the business exits the estate cleanly, the family receives liquidity instead of an illiquid interest, and the surviving owners retain control.

The mistake is treating a buy-sell as a one-time document you sign at formation. Businesses change. Owners change. Valuations change. A buy-sell agreement that was excellent when it was drafted can become useless within five years if no one revisits it. Put it on the same review cycle as your estate plan and your insurance — every two to three years, and after every major event.

For the broader landscape of ownership transitions, see our business succession guide. For funding — the piece that most owners get wrong — start with the life insurance guide.