Dental Practice Startup Costs: The IRC 195 Deduction, Build-Out Classification, and First-Year Tax Planning

Opening a dental practice from scratch means spending money for months, sometimes a year or more, before a single patient walks through the door. Market research, a site selection consultant, a lease deposit, an architect, a contractor, six figures of equipment, and staff hired weeks early to train on the practice management system all hit the bank account before the practice generates a dollar of revenue. Every one of those costs is deductible somewhere on the return, but the code section, the timing, and the dollar limits differ depending on what the cost actually is. Getting the classification right in year one determines whether the practice claims tens of thousands of dollars in deductions when they are most useful, against a business that typically shows little or no income yet, or spreads the same deductions thinly over 15 years. This guide covers the startup cost deduction, how to classify build-out spending, the tradeoffs between buying and leasing equipment, working capital planning, and the accounting and payment decisions that shape a new practice’s first return.

What startup cost deduction does a new dental practice get?

IRC 195 allows a new business to immediately deduct up to $5,000 of costs that would have been ordinary and necessary business expenses under IRC 162 had the business already been operating, but that are paid before the business begins. The $5,000 immediate deduction phases out dollar for dollar once total qualifying startup costs exceed $50,000, disappearing completely at $55,000. Whatever remains after the immediate deduction is amortized on a straight-line basis over 180 months (15 years), beginning in the month the practice opens its doors to patients.

For most dental startups, the total of pre-opening rent, training payroll, marketing, and consulting fees runs well past $55,000, which means the $5,000 immediate deduction is usually unavailable and the entire amount amortizes instead. That still produces a real, recurring deduction every month for the next 15 years; it just does not front-load into a single large year-one write-off the way equipment does.

A separate $5,000 immediate deduction exists for organizational costs, the expenses of forming the legal entity itself, under IRC 248 for a corporation or IRC 709 for a partnership or multi-member LLC. State filing fees, the attorney’s fee for drafting the operating agreement, and the initial accounting setup fall into this bucket, and it carries the same $50,000 phase-out, calculated separately from the IRC 195 total. Because entity formation for a single dental practice rarely exceeds $8,000 to $10,000, most owners get the full $5,000 immediate deduction here even when the IRC 195 total is fully phased out.

One procedural point: the election to apply the $5,000 deduction and 180-month amortization is technically required, but a deemed election protects a taxpayer who files without attaching a formal statement, treating the taxpayer as having made the standard election automatically. Once made, the treatment is locked in and generally cannot be changed without IRS consent.

What counts as a startup cost, and what doesn’t?

The dividing line under IRC 195 is what kind of expense it is, not when the check clears. A cost paid the week before opening and the same cost paid once the practice is running are treated identically in nature; the only thing IRC 195 changes is the timing of the deduction.

Costs that typically qualify as IRC 195 startup expenses include the demographic and competitive market research done before choosing a location, the site selection and lease negotiation process, pre-opening rent between signing the lease and seeing the first patient, wages paid to staff hired early to train on the practice management system and sterilization protocols, a transition consultant engaged to set fee schedules and build recall systems, travel to manufacturer equipment training, and pre-opening marketing, meaning the direct mail campaign, paid search budget, website build, and open house that run before the first patient is ever seen.

Costs that do not qualify, even though paid before opening day, include equipment purchases of every kind (chairs, delivery units, autoclaves, compressors, digital sensors), capital assets depreciated under IRC 168; the office build-out itself, discussed below; entity formation costs, which fall under IRC 248 or IRC 709 instead; and supplies purchased before opening but consumed after, deductible as materials and supplies when used, not as startup costs at all. Misclassifying any of these into the IRC 195 bucket locks a large deduction into 180-month amortization when it should have been available in full in year one, one of the more expensive mistakes a new practice makes on its first return.

How are dental office build-out costs classified?

The build-out is usually the second-largest capital outlay after equipment, and it gets a materially better tax result than most new owners expect, provided it is classified correctly. Operatory construction, including demolition, framing, plumbing for suction lines and compressed air distribution, dedicated electrical circuits, HVAC modifications, flooring, and built-in cabinetry, is an interior improvement to a nonresidential building and is classified as Qualified Improvement Property (QIP) under IRC 168, not as a startup cost and not as the 39-year real property class that applies to the building shell itself.

QIP carries a 15-year MACRS recovery period on paper, but it is eligible for 100% bonus depreciation, meaning the entire build-out cost can be deducted in the year the space is placed in service rather than spread over 15 years. A practice that spends $400,000 on a four-operatory build-out deducts the full $400,000 in year one, not $26,667 per year for 15 years. This is the single largest deduction most new dental practices will ever claim, and also the one most frequently misclassified when a preparer unfamiliar with QIP lumps the entire build-out into the 39-year bucket by default.

The distinction from Section 1250 property matters at the margins. Structural components of a building the practice owns outright, such as the roof, exterior walls, and core electrical and plumbing systems as originally installed, remain 39-year Section 1250 real property. QIP applies specifically to interior improvements made after the building was first placed in service, which describes virtually every dental operatory build-out inside a leased shell space, and does not extend to enlarging the footprint, elevators, or changes to the internal structural framework.

State conformity is worth checking before assuming the full deduction applies everywhere. States that decouple from federal bonus depreciation, California among them, require the practice to depreciate the same QIP over its 15-year federal recovery period for state purposes even while claiming the full bonus deduction federally. This is a routine adjustment, not a problem, but it should be built into the first-year state estimate rather than discovered when the state return is prepared.

Should I buy or lease my dental equipment?

Equipment is the largest category of spending for most new practices, commonly $250,000 to $600,000 for a modest multi-operatory build depending on how much imaging and CAD/CAM technology is included, and the purchase-versus-lease decision changes both the tax treatment and the cash flow profile of the first year significantly.

Purchasing equipment outright, whether with cash or with a bank or SBA loan, makes the practice the owner of the asset from day one. The full cost is eligible for IRC 179 expensing, capped at $2,500,000 for 2025 (doubled by the One Big Beautiful Bill Act) and limited to the practice’s taxable income, or for 100% bonus depreciation under IRC 168(k), which has no income limitation and can create or increase a net operating loss. Because most new practices show a loss in year one before Section 179’s income limitation even becomes relevant, bonus depreciation typically does the work: the full equipment cost is deducted in the year it is placed in service, regardless of profitability. Loan interest on equipment financing is separately deductible under IRC 163, and the business interest limitation in IRC 163(j) is irrelevant for a practice of ordinary size, applying only above $32 million in average gross receipts (for 2026).

Leasing changes the picture. A true operating lease (the practice never owns the equipment and returns or renews at the end of the term) produces a straightforward rent deduction under IRC 162 spread evenly over the lease term, with no depreciation available to the lessee, since the lessor retains ownership for tax purposes. A capital lease or a lease structured as a financing arrangement (a $1 buyout lease, where the practice effectively owns the equipment at the end for a nominal payment) is treated as a purchase from the start: the practice capitalizes the equipment, claims depreciation as if it had bought the asset outright, and deducts only the interest component of each payment, not the full payment.

The practical tradeoff is speed of deduction against preservation of cash. Buying produces the largest possible first-year deduction but requires capital or debt capacity up front. A true operating lease preserves cash in the critical early months but spreads the tax benefit over the lease term instead of concentrating it in year one. Many new practice owners split the decision: buy the core, long-life equipment where accelerating the deduction matters most, and lease equipment most likely to be replaced within a few years, where preserved cash matters more than accelerating a deduction on an asset that may be swapped out before it is fully depreciated anyway.

How much working capital does a new practice need?

Working capital planning is where the tax analysis meets the practical reality of running the practice through its first patient cycle. A new dental practice typically takes six to twelve months to reach a stable patient volume and predictable collections, and insurance reimbursement in particular lags treatment by 30 to 60 days. Payroll, rent, lab fees, and supplies all have to be funded during this ramp-up from a combination of the owner’s remaining capital, a working capital line of credit, and, often, a portion of the SBA loan proceeds earmarked for operating expenses rather than equipment or build-out.

A reasonable planning target for a new general practice is six months of fixed operating costs held in reserve or available through an undrawn line of credit at the moment the practice opens: rent, base payroll, minimum debt service, insurance premiums, and a baseline supply order. For a practice with $25,000 to $35,000 in monthly fixed costs, that translates to $150,000 to $210,000 in coverage, separate from the capital already spent on the build-out and equipment. Underfunding this line item is one of the more common reasons a well-designed practice runs into cash trouble in its first year, not because the tax planning was wrong, but because the deductions a practice is entitled to do not arrive as cash. A large bonus depreciation deduction reduces the tax bill; it does not pay January’s payroll.

Which accounting method should a new practice choose?

Most dental practices should elect the cash method from the outset, and IRC 448 is the provision that makes this straightforward for a business of typical size. IRC 448 generally bars C corporations and partnerships with a C corporation partner from using the cash method once average annual gross receipts exceed a threshold that is $31 million for 2025, but it does not restrict the cash method for a sole proprietorship, an S-corp, or a partnership without a corporate partner below that threshold, which covers essentially every dental practice regardless of entity structure.

The cash method recognizes income when collected and expenses when paid, simpler to administer and, for a new practice with a slow collections ramp, tends to defer taxable income relative to when it is actually billed. The accrual method recognizes income when earned, not when paid, which can accelerate taxable income ahead of actual cash collection during the exact period a new practice can least afford it. A practice electing accrual in its first year, without a strong reason tied to bank covenants or a planned near-term sale, is choosing the method more likely to create a tax bill on money not yet in the bank.

The accounting method is elected on the first return filed and generally requires IRS consent (via Form 3115) to change later, so this decision should be settled before the first return is prepared, working from the entity structure and projected first-year cash flow rather than defaulting to whatever the bookkeeping software uses out of the box.

How do estimated tax payments work in the first year?

A new practice’s income pattern in year one, typically a loss or small profit driven down by bonus depreciation, followed by a much larger profit in year two once the deductions are used and patient volume stabilizes, makes standard estimated tax planning trickier than it looks. Underpaying estimated taxes in year two because the owner is anchored to a memory of a loss-heavy year one is a common and avoidable mistake.

For a pass-through entity, estimated tax is paid by the owner personally based on projected individual income, except in states with a pass-through entity tax election that shifts part of the payment to the entity level. The standard safe harbor rules apply: paying in 100% of the prior year’s tax liability (110% above $150,000 in prior-year AGI) protects against an underpayment penalty, but a new dentist coming out of employment or a residency has no relevant prior-year practice-owner liability to base that on, so the safe harbor calculation for year one often looks to the individual’s prior W-2 or associate income instead. Once the practice is in its second full year and the large first-year bonus depreciation deductions are gone, projected income can jump sharply, and quarterly estimates should be recalculated mid-year rather than left on autopilot.

What first-year tax planning moves matter most?

The timing of equipment purchases within the first year is worth deliberate planning rather than simply buying everything as soon as needed. Because bonus depreciation applies in the year an asset is placed in service, not the year it is ordered, a dentist anticipating a stronger-than-projected first year may want to accelerate a planned purchase into that year to offset the higher income, while a dentist expecting a slower ramp may prefer to spread purchases across the first two years rather than concentrating a large loss in year one against income that isn’t there yet.

Choosing the entity structure and making any S-corp election before the practice opens, rather than after the first year closes, avoids the complications of running startup costs through an individual before the entity legally exists. The considerations behind that choice are covered in the entity structure guide. Once the practice is past its opening year, the full landscape of ongoing deductions is covered in the tax deductions guide.

What should I do next?

Before the first return is filed, classify every dollar of pre-opening spending into its correct bucket: IRC 195 startup costs, IRC 248 or IRC 709 organizational costs, QIP build-out costs eligible for bonus depreciation, and equipment. Decide the accounting method with the entity structure and first-year cash flow projection in view, not by default. Size the working capital reserve separately from the build-out and equipment budget, since the deductions a practice earns do not arrive as cash. And revisit the estimated tax calculation once real numbers replace the opening projection, since a strong second year after a loss-heavy first is the most common way a new owner gets caught by an underpayment penalty.

If you own the building the practice will operate out of, the classification of the real estate is a separate and more involved question from the build-out inside a leased space, covered in the real estate ownership guide.

These companion guides cover the connected decisions:

• Dental practice entity structure: LLC, S-corp, partnership, and when to change, the entity decision that should be settled before startup costs start hitting the practice’s books
• Dental practice tax deductions, the ongoing deduction landscape once the startup phase ends and the practice is in normal operations
• Dental practice startup costs: new practice vs acquisition, a side-by-side comparison for a dentist still deciding between building from scratch and buying an existing practice
• Owning your dental office building, the self-rental rules and cost segregation analysis for a dentist who owns or is buying the real estate rather than leasing it
• Dental practice valuation and sale, the eventual exit that the entity and cost basis decisions made in year one continue to affect

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