Dental Practice Buy-Sell Agreement: Financial Planning Guide

Your partner is diagnosed with a progressive neurological condition and can't practice. Who buys their 50% stake in the practice — you, or the practice entity? At what price? On what timeline? And who funds the transaction? Without a buy-sell agreement, none of those questions have answers. The result: a forced sale to an unknown buyer, years of litigation, and a practice that loses patients while attorneys argue.

A buy-sell agreement is the legal contract that defines exactly what happens when a partner leaves the practice involuntarily (death, disability) or voluntarily (retirement, departure). It's the most important document dental practice co-owners will ever sign — and one of the most commonly skipped.

The five trigger events

A well-drafted buy-sell agreement covers all five scenarios where ownership must change hands:

1. Death. The most common trigger. The deceased partner's estate inherits their practice ownership — which typically means non-dentist heirs hold equity in a PLLC licensed to practice dentistry. Most states prohibit non-dentist ownership of dental practices. The buy-sell forces a buyout before that becomes a crisis.
2. Total disability. The dental-specific trigger. If your partner can no longer practice due to injury or illness, the practice still has expenses — but now only one dentist is generating revenue. The buy-sell defines when disability triggers the buyout (typically after 12–24 months of total disability) and at what price.
3. Voluntary retirement or exit. A partner who wants to sell their stake back or to co-owners. Without a buy-sell, this can turn into a negotiation that drags on for years. With one, the mechanism (right of first refusal, valuation formula, payment timeline) is pre-agreed.
4. Involuntary exit. Loss of dental license, personal bankruptcy, divorce proceedings that could expose the practice equity to a non-dentist spouse, or criminal conviction. These events are rare, but the consequences of not having exit terms defined are severe.
5. Deadlock. In 50/50 partnerships, where you and your partner disagree on a practice-defining decision and can't resolve it. A buy-sell can include a "shotgun clause" or mediation requirement before either partner can force a buyout.

Two structures — the tax differences matter

Buy-sell agreements are funded two ways. The structure determines tax treatment for surviving owners and for the departing owner's estate.

Why the basis difference matters: When you eventually sell the practice, you pay capital gains tax on the difference between your sale price and your cost basis. In a cross-purchase, your basis in the portion you acquired at your partner's death reflects what you paid — fair market value. In an entity redemption, your basis in your original ownership stake stays low. Over a 20-year practice, this difference can cost surviving partners $50,000–$150,000 in extra capital gains tax at sale.

Entity redemption is administratively simpler (fewer policies, one owner) and is often recommended when there are more than two partners — with three partners, cross-purchase requires six policies; with four, it requires twelve. For two-partner dental practices, cross-purchase usually wins on tax grounds. A hybrid (wait-and-see) agreement gives the practice the option to redeem first, with the surviving partners buying any remainder — preserving flexibility to choose the better structure at the time of the triggering event.

The disability trigger: the most important clause for dentists

Death triggers are straightforward to fund with life insurance. Disability triggers are harder — and for dentists, more statistically likely. You're 3–4× more likely to be disabled during your career than to die during it.²

The buy-sell disability trigger requires careful drafting on several dimensions:

• Definition of disability. Must be "own-occupation, own-specialty" — the same standard you'd demand on your personal disability insurance. "Unable to perform the material duties of a dentist" is not enough; your partner might be unable to treat patients but still technically able to do administrative work. The definition should require inability to perform clinical dentistry specifically.
• Waiting period. Most buyout policies and agreements use 12–24 months of continuous total disability before the buyout obligation triggers. This avoids forcing a buyout for temporary injuries while ensuring certainty if disability is permanent.
• Valuation timing. Is the practice valued at the time disability is declared, or when the waiting period expires? Practice value can change materially if a key dentist is absent for 18 months.

Disability buyout insurance

Life insurance funds the death trigger. Disability buyout insurance (sometimes called "business overhead expense buyout" or "key person disability") funds the disability trigger. Key features:

• Purchased to match the expected buyout obligation under the buy-sell agreement.
• Typically available in benefit amounts up to $750,000–$1,000,000 per insured partner, depending on carrier and practice value.
• Benefits are paid in a lump sum or installments after the defined waiting period.
• Tax treatment: If partners pay premiums personally with after-tax dollars, benefits received are income-tax-free. If the practice entity pays premiums and deducts them as a business expense, benefits received are taxable as ordinary income. Most dental practice attorneys recommend the former — personal premium payment preserves tax-free benefit treatment.
• Premiums for disability buyout insurance are not deductible when paid individually (unlike individual disability income coverage under some S-corp structures).

Practice valuation in the buy-sell

The valuation method is often where buy-sell agreements fail. There are three approaches, each with significant downsides if not maintained:

Most dental attorneys recommend a hybrid approach: a formula as the baseline (collections multiple adjusted by EBITDA margin), with each partner having the right to demand a formal appraisal within 30 days if they dispute the formula result. This prevents either party from gaming the formula while avoiding delay if both parties accept it.

Whatever method you choose, include a mandatory annual review clause. If the practice grows significantly or partners' equity stakes change, the buy-sell needs to keep pace.

Life insurance sizing for the buy-sell

Each policy needs to be large enough to fund the buyout at anticipated practice value — not today's value, but the value at the time the trigger event most likely occurs (10–20 years from now for younger partners). Common mistakes:

• Underfunding at purchase. Buying a $500K policy for a $1.2M practice and never updating it. The surviving partner has to fund the gap from personal savings or practice cash flow.
• Cross-ownership tax trap in entity redemption. If policies are poorly structured and transferred between owners, IRC §101(j) can make death benefits partially taxable. Avoid post-issuance policy transfers when possible.
• Forgetting to update policies when the valuation changes. Tie annual insurance review to the same calendar event as the buy-sell valuation review.

Common buy-sell mistakes in dental practices

1. Signing once and never reviewing. The agreement is drafted when both partners are associates buying into a small practice. Eight years later, the practice is doing $3.2M in collections, and the buy-sell still references a $900K fixed price and $500K policies.
2. No disability trigger clause at all. Many boilerplate buy-sell agreements downloaded from the internet only address death. Disability is the more likely event — and the harder one to handle without a defined mechanism.
3. Unclear disability definition. If the definition of disability in the buy-sell doesn't match the definition in the disability buyout insurance policy, there can be a gap: the insurance pays, but the buy-sell doesn't trigger (or vice versa).
4. Letting a key-person policy lapse. Insurance premiums are easy to cut when cash flow is tight. The practice that stops paying the buyout insurance premium has eliminated the funding mechanism for the agreement — but the legal obligation to buy out a disabled partner remains.
5. Drafting the buy-sell without coordinating with the financial advisor. Tax treatment, insurance sizing, and retirement plan impact all depend on details of the structure. An attorney who drafts without financial advisor input may build a legally sound agreement with suboptimal tax outcomes.