S-Corp vs PLLC vs Sole Prop for a Dental Practice: Which One Actually Fits

Most entity guides start with the tax question: LLC or S-corp, which one saves more money. For a dentist, that question comes second. The first question is what your state’s dental board will let you own, because a dental practice is a licensed professional service, and almost every state restricts who can hold ownership in one. The tax analysis, the self-employment tax savings, the qualified business income deduction, all of it sits on top of a licensing framework that narrows the choices before a single tax return gets filed. This guide works through the decision in the order it actually needs to happen: what the state allows, what the S-corp election does to your payroll taxes once you’re inside an allowed structure, and when the paperwork and payroll cost of the election is worth it.

What entity choices does a dentist actually have?

A new dentist opening a first practice faces four structures in practice, and two of them are rarely the right answer.

Sole proprietorship is the default if nothing is filed. There’s no separation between the dentist’s personal assets and the practice’s liabilities, no ability to elect S-corp treatment, and every dollar of net income is subject to self-employment tax. It’s common for the first several months of a startup practice because there’s nothing to set up, but almost every dentist moves off it once the practice generates real income, both for liability protection and for the tax planning options a formal entity opens up.

A general C-corporation is almost never the right structure for a dental practice. C-corp income is taxed at the entity level and again when distributed to the owner as a dividend, and unlike a personal service corporation’s flat rate under prior law, there’s no offsetting benefit that makes double taxation worthwhile for a practice whose income is meant to reach the dentist personally. C-corps show up in dental practice history mostly as legacy structures from decades ago, or in specific personal goodwill planning around a sale, which is a narrow exception, not a starting point.

That leaves two real options: a PLLC or PC taxed as a disregarded entity or partnership (no S-corp election), or that same entity with an S-corp election layered on top. The entity form (PLLC vs PC) is a state law question. The S-corp election is a federal tax question made by filing Form 2553. They are independent decisions, and the state law question comes first.

Must a licensed dentist own the practice?

In most states, yes, and this is the constraint that shapes everything downstream. State dental practice acts generally prohibit anyone other than a licensed dentist from owning a dental practice or holding a controlling interest in the entity that operates one. The professional limited liability company (PLLC) exists specifically to accommodate this rule: it gives licensed professionals the liability protection of an LLC while restricting membership to people who hold the relevant license.

The specific entity form allowed varies by state. Texas, New York, and Florida permit PLLCs for dentists. California does not authorize PLLCs for licensed professionals at all and instead requires a professional corporation (PC), which can elect S-corp tax treatment the same way a PLLC can, the corporate law wrapper is different but the federal tax treatment is not. A handful of states use different naming conventions again. Before an entity gets formed, check the specific dental practice act in your state, because the IRS will process an S-corp election for whatever entity you send it, but the state licensing board will not recognize an improperly formed entity as a legitimate practice owner, and that’s a problem no federal filing fixes.

This restriction is also why dental service organization (DSO) arrangements are structured as management agreements rather than direct equity ownership in most states. A private equity-backed DSO generally cannot hold a direct ownership stake in the clinical PLLC or PC because it isn’t a licensed dentist. Instead, the DSO owns a separate management company that contracts with the dentist-owned clinical entity to provide non-clinical services (billing, marketing, HR, equipment procurement) for a fee. The clinical entity, and the tax analysis in this guide, still belongs to the licensed dentist.

There’s a second reason the entity form matters beyond licensing: eligibility for the S-corp election itself. IRC 1361 limits S-corp shareholders to individuals, certain trusts, and estates, no more than 100 shareholders, and only one class of stock. A private equity fund or a corporate DSO cannot be a shareholder in an S-corp regardless of state dental board rules. This is a second, independent reason the DSO relationship is structured as a contract rather than equity: even where a state theoretically allowed non-dentist ownership, bringing in an institutional investor as a direct owner would blow up the practice’s S-corp eligibility.

How does the S-corp election reduce self-employment tax?

Once the entity form is settled (PLLC or PC, owned by the licensed dentist), the remaining question is whether to file Form 2553 and elect S-corp treatment. Without the election, all net income from the practice is subject to self-employment tax under IRC 1402: 12.4% Social Security tax up to the annual wage base, plus 2.9% Medicare tax with no cap, plus an additional 0.9% Medicare surtax above $200,000 (single) or $250,000 (married filing jointly).

The S-corp election changes the mechanics without changing the total income. The dentist-owner becomes an employee of their own entity, receives a W-2 salary through payroll, and that salary is the only piece of income subject to employment tax. IRC 3121 defines what counts as wages for FICA purposes, and only the salary meets that definition. The remaining profit is distributed as a shareholder distribution, reported on the K-1 or as a dividend from the entity, and it’s not subject to FICA at all. That gap, between total net income and the salary the dentist actually needs to pay themselves, is where the savings come from.

The catch is that the salary has to be defensible as reasonable compensation for the work the dentist actually performs, and dentistry is a field where the IRS has unusually good data to challenge a salary that looks too low.

What counts as reasonable compensation under IRC 3121?

Reasonable compensation isn’t defined by a formula in the Code. It’s a facts-and-circumstances standard that asks what an unrelated party would pay the dentist for the clinical, administrative, and management work actually performed, and the IRS enforces it aggressively in dentistry because there’s more third-party benchmark data available than in almost any other small business category.

The American Dental Association publishes annual compensation surveys by specialty and region. Dental staffing agencies and practice management consultants publish their own benchmarks. Associate dentist compensation, which commonly runs 25% to 35% of the associate’s personal production, provides a floor: if an associate earns that percentage for clinical work alone, an owner performing the same clinical work plus management and business development duties is worth at least as much, usually more.

The failure mode the IRS catches most often is a salary set too low relative to the practice’s production. A dentist producing $900,000 personally and paying themselves a $60,000 S-corp salary is effectively claiming their clinical output is worth less than an entry-level hygienist’s pay, and that position does not survive examination. The consequence isn’t just back taxes on the reclassified amount: it’s back FICA, penalties, and interest, potentially across multiple open tax years, calculated on every distribution the IRS successfully reclassifies as wages.

The safer approach documents the number before it’s used, not after an audit starts. A defensible file includes the ADA or regional survey data for the dentist’s specialty, comparable associate compensation in the same market, and a note on what portion of the practice’s revenue reflects the owner’s personal clinical production versus the work of associates and hygienists. That documentation costs an afternoon. Reconstructing it during an IRS examination, years later, costs considerably more.

Does the QBI deduction under IRC 199A help dentists?

Dentistry is classified as a health service, which puts it in the specified service trade or business (SSTB) category under IRC 199A. SSTB classification matters because the 20% qualified business income deduction, which is otherwise one of the most valuable pass-through tax breaks available, phases out at higher taxable income and disappears completely above the top of the phase-out range, regardless of entity structure.

For 2026, the phase-in begins once taxable income exceeds $201,750 for single filers or $403,500 for married filing jointly, with a $75,000 (single) or $150,000 (joint) phase-in range. Above $276,750 (single) or $553,500 (joint), the QBI deduction for an SSTB is fully phased out. These thresholds are indexed for inflation and adjust most years.

This creates two very different pictures depending on where a dentist’s income falls. A newer practice owner, an associate still building a patient base, or a dentist whose household taxable income sits below the lower threshold can potentially claim the full 20% deduction on qualifying pass-through income, which stacks on top of whatever the S-corp election is already saving on FICA. A more established solo owner, particularly one filing jointly with a working spouse, is commonly well past the upper threshold, in which case the QBI deduction contributes nothing no matter how the entity is structured or how the salary is set.

How much liability protection does each structure provide?

A PLLC or PC creates a liability shield between the entity’s business debts and the dentist’s personal assets. A judgment against the practice arising from a lease dispute, an employment claim from a staff member, or a slip-and-fall in the waiting room generally can’t reach the dentist’s personal home, personal investment accounts, or other assets outside the practice. A sole proprietorship offers none of this: every practice liability is a personal liability.

What no entity form protects against is the dentist’s own clinical negligence. Malpractice liability follows the individual who provided the care, and that exposure exists whether the dentist operates as a sole proprietor, a PLLC, or a PC with an S-corp election. Professional liability insurance, not entity structure, is what manages that risk. This is a common point of confusion: forming a PLLC protects the dentist’s house from a slip-and-fall claim against the practice, but it does not protect the dentist from a malpractice judgment arising from their own treatment of a patient. Multi-owner practices add another layer worth naming here: an owner in a multi-dentist PLLC generally isn’t personally liable for a co-owner’s malpractice, but that protection depends on the entity being properly maintained, adequately capitalized, and not used as an alter ego for personal transactions. A poorly maintained entity is one a plaintiff’s attorney can sometimes pierce.

When does an S-corp election make sense for dentists?

The state law question settles itself first: form the PLLC, PC, or whatever structure your state’s dental board requires for a licensed-owner practice. The S-corp election is the second, separate decision, and the short answer is that it depends on net income, not on any fixed rule.

Below roughly $80,000 to $100,000 in net income before owner compensation, the added payroll and compliance cost of an S-corp typically consumes most or all of the FICA savings, and the reasonable salary requirement doesn’t leave enough room between the salary and total income to produce meaningful distributions. Between roughly $100,000 and $200,000, the election generally produces a modest but real net benefit, often in the range of $1,000 to $5,000 a year once compliance costs are subtracted, as shown in the first hypothetical above. Above $200,000, the savings scale up meaningfully, often into five figures annually, and the QBI question becomes the second variable that determines whether there’s additional value sitting on top of the FICA savings.

A dentist evaluating this shouldn’t rely on a single rule of thumb from a blog post, including this one. The break-even point depends on the specific practice’s net income, the defensible reasonable compensation figure for that dentist’s market and specialty, the household’s full tax picture including a spouse’s income, and the state’s conformity to federal entity tax treatment. A written calculation using the practice’s actual numbers is worth doing before filing Form 2553, not after.

What should I do next?

Start with your state’s dental practice act. Confirm the entity form your state requires for a licensed-owner dental practice, whether that’s a PLLC, a PC, or something specific to your jurisdiction, before anything else gets decided. Once that’s settled, run the S-corp math against your actual net income and a defensible reasonable compensation figure for your specialty and market, not a number picked to hit a round target.

If you’re weighing whether to buy your office space through a separate entity once the practice structure is settled, the ownership-versus-lease analysis runs on a parallel track, with its own self-rental and depreciation questions: see how physicians weigh owning versus leasing practice real estate for how that decision interacts with entity structure. If your practice is bringing in a second owner, dental associate compensation and buy-in tax treatment covers how the buy-in is valued and taxed once the entity question above is answered. And once the entity is set, dental practice retirement plans covers how much of the income the S-corp salary produces can be sheltered through a 401(k), profit-sharing, or cash balance plan stack. For the multi-dentist partnership structure and what happens to entity choice when the practice eventually sells, see dental practice entity structure: LLC, S-corp, and partnership. And for how the equipment purchases that fund a growing practice get deducted once the entity is in place, see dental equipment depreciation and Section 179.

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.