Deferred Purchase Price: Installment Method, 453A, and Earnouts

The tax treatment of a deferred purchase price in a business sale depends on two things: whether the deferred amount is fixed or contingent, and which side of the deal you are on. Sellers usually recognize gain as payments arrive under the installment method, while buyers add fixed deferred amounts to their asset basis at closing and wait to capitalize contingent amounts until the obligation becomes fixed. Layered on top are imputed-interest rules, an interest charge on large installment obligations, and the ever-present risk that an earnout gets recharacterized as ordinary compensation.

Fixed Obligations vs. Contingent Consideration

The tax rules split cleanly along one line. A seller note has a defined principal amount, a stated interest rate, and a payment schedule; everyone knows the number at closing. An earnout, by contrast, pays only if the acquired business hits post-closing targets tied to revenue, EBITDA, gross margin, or similar metrics. Outside of life sciences, earnout periods commonly run about 24 months; life sciences deals often stretch three to five years or longer.

That distinction between a known amount and a contingent one drives almost every timing question that follows.

Seller’s Installment Method

If you sell a business and receive at least one payment after the close of the tax year in which the sale occurs, you report the gain on the installment method by default. No election is required to use it.¹

The mechanic is a gross profit ratio. Take gross profit (total selling price minus adjusted basis and selling expenses) and divide by the total contract price. Multiply that ratio by each payment you receive to get the gain recognized that year. A 60 percent ratio on a $100,000 payment produces $60,000 of gain.¹

Interest received on a seller note is reported separately as ordinary interest income. It never runs through the gross profit ratio.

Gain That Can’t Be Deferred

Several categories must be reported in full in the year of sale, no matter when the money actually shows up:

Depreciation recapture. Gain attributable to prior depreciation deductions on equipment, vehicles, or other depreciable property is recognized in the year of sale.²
Inventory. Sales of inventory items cannot use the installment method.¹
Publicly traded securities. Stock or securities traded on an established market are excluded.¹

A typical business sale splits along this line. Gain from depreciable assets hits the year-one return; gain from goodwill and other non-depreciable assets rides the installment schedule.

Contingent Payment Sales

Earnouts complicate the gross profit ratio because the total selling price is unknown at closing. Treasury regulations set out three cases. If the earnout has a stated maximum price, that maximum is the assumed selling price and basis is allocated accordingly. If there is no maximum but a fixed payment period, basis is spread evenly across the years payments may be received. If neither a maximum nor a fixed period exists, basis is recovered ratably over 15 years.³

If the maximum selling price is later reduced because a contingency won’t be met, the gross profit ratio is recalculated for that year and all future payments.

Electing Out

The installment method applies automatically, but you can elect out. The election must be made on or before the due date (including extensions) of the tax return for the year of sale, and once made can only be revoked with IRS consent.⁴

Sellers elect out when they expect tax rates to rise, when expiring loss carryforwards can absorb the gain, or when the section 453A interest charge below makes deferral uneconomic.

Related Party Sales

If you sell property on the installment method to a related person and that person resells the property within two years, the amount realized on the second sale is treated as if you received it at the time of the resale. This blocks two-step transactions that would let affiliated parties cash out while the original seller kept deferring.⁴ Related parties for this purpose include family members, controlled entities, and other relationships defined by the tax code’s attribution rules.

The 453A Interest Charge on Large Installment Obligations

Section 453A imposes a special interest charge when installment obligations from sales exceeding $150,000 remain outstanding and the taxpayer’s total outstanding installment obligations that arose during the tax year exceed $5 million at year-end. The charge is meant to offset the time-value benefit of stretching a large tax liability across many years.⁵

The calculation runs in layers. First, an “applicable percentage” equals the portion of total outstanding installment obligations exceeding $5 million divided by the total face amount outstanding. Next, the “deferred tax liability” equals the unrecognized gain on the note multiplied by the maximum tax rate for your filing type. The interest charge itself is the applicable percentage of that deferred tax liability, multiplied by the IRS underpayment rate for the last month of the tax year.⁵

On eight-figure transactions, this charge takes a real bite out of the deferral benefit. Model it before assuming the installment method is the better path.

The Pledging Trap

Using an installment obligation covered by section 453A as collateral for a loan triggers a deemed payment. The loan proceeds are treated as if received directly from the buyer, and gain is recognized accordingly.⁶

The deemed payment can’t exceed the total contract price minus payments already received, and total recognized gain from pledging plus actual payments can never exceed the total gain from the sale. Still, borrowing against an installment note accelerates the very tax the seller was trying to defer.

Imputed Interest on Deferred Payments

If a deferred payment arrangement charges no interest or charges interest below the applicable federal rate, the IRS recharacterizes part of each payment as interest. Without this rule, parties could disguise an interest-bearing loan as an interest-free installment of the purchase price and convert ordinary interest income into lower-taxed capital gain.

Two code sections do the recharacterization. Section 1274 applies to sales where total payments exceed $250,000, using the original issue discount framework. The test rate depends on the term: short-term AFR for notes of three years or less, mid-term for three to nine years, long-term for over nine years.⁷

Section 483 applies to smaller sales where total consideration is $250,000 or less. The mechanics differ slightly, but the outcome matches: interest is imputed at the AFR, becoming ordinary interest income to the seller and deductible interest expense to the buyer.⁸

The AFRs update monthly, so pull the current IRS revenue ruling before pricing a seller note.⁹

Buyer’s Side: Basis, Deductions, and Allocation

For a fixed seller note, the full principal amount is included in the buyer’s tax basis of the acquired assets at closing. The buyer doesn’t wait until the note pays off. The interest portion of each payment is deductible as a business expense when paid or accrued, depending on the buyer’s accounting method.

Earnouts work differently. Because the payment amount is uncertain, the contingent portion is generally not included in basis until the obligation becomes fixed. You can’t depreciate or amortize an amount that might never be owed. When an earnout payment is eventually made, the buyer capitalizes it into the acquired assets’ basis using the same allocation methodology applied at closing.

Allocating Across the Seven Asset Classes

Both buyer and seller allocate total consideration among seven asset classes using the residual method. The allocation begins with cash and cash equivalents (Class I) and moves through actively traded securities, receivables, inventory, and other tangible and intangible assets, ending with goodwill and going-concern value (Class VII). Each class absorbs consideration up to the fair market value of assets in it, and any remainder cascades to the next class.¹⁰

The allocation drives future deductions. Equipment might be depreciated over five or seven years. A building over 39. Goodwill and most other intangibles are amortized ratably over 15 years.¹¹

When a later earnout payment adds to the total purchase price, the buyer reallocates that additional amount across the same asset classes. Because tangible assets were usually already valued at fair market value at closing, the incremental earnout typically lands in Class VII as additional goodwill and starts a new 15-year amortization stream in the month of payment.

Earnout Recharacterization Risk

This is where sellers most often get blindsided. If the IRS concludes that an earnout payment is disguised compensation rather than part of the purchase price, the whole payment is taxed as ordinary income. For a seller expecting long-term capital gain rates, the reclassification can nearly double the effective tax rate on the earnout portion.

Courts and the IRS weigh several factors:

Employment contingency. If the seller must remain employed to receive payments, that points hard toward compensation. Payments that continue regardless of employment status look like deferred purchase price.
Proportionality. Payments distributed to all former shareholders in proportion to their ownership stakes point toward purchase price treatment. Payments going only to shareholders who continue working point toward compensation.
Separate reasonable compensation. If selling shareholders who stay on are already paid market-rate salaries for their post-closing roles, the earnout is more defensibly purchase price. If the earnout is their only pay for services, the IRS sees compensation dressed as deal consideration.
Negotiation history. An earnout introduced to bridge a valuation gap supports purchase price treatment. One structured as a retention incentive looks like a bonus.
Metric type. Payments tied to company-wide financial metrics (total revenue, EBITDA) lean capital gain. Payments tied to individual performance lean compensation.

The safest structure has every former shareholder participate based on ownership percentage, ties payments to objective company-level financial metrics, and states in the agreement that payments are unaffected by any individual’s employment status. Even then, keep documentation of the negotiation history in case the IRS raises the question later.

Reporting the Sale

Form 6252

Sellers reporting gain under the installment method file Form 6252 with their federal return for the year of sale and every subsequent year in which a payment is received. The form runs the gross profit ratio calculation and tracks remaining gain to be recognized in future years.¹²

Form 8594

Both buyer and seller file Form 8594 when a group of assets making up a trade or business changes hands and the buyer’s basis is determined by the amount paid. The form reports how the purchase price was allocated among the seven asset classes. Each party files it with their return for the year of sale, and an amended Form 8594 must be filed in any later year when contingent consideration changes the total amount allocated.¹⁰

Buyer and seller allocations should match. A mismatch flags the transaction for IRS scrutiny, because one side is likely claiming deductions inconsistent with the other side’s gain reporting.

A Note on Financial Statement Treatment

Everything above is tax. Financial-statement accounting under ASC 805 runs on a separate track: the buyer records the full fair value of all consideration transferred on the acquisition date, including deferred amounts, and contingent consideration classified as a liability is remeasured to fair value at every reporting date until the contingency resolves, with changes running through earnings. Book basis and tax basis in a deferred-price deal will diverge from day one, and the reconciliation is its own project.

1
Internal Revenue Service. Publication 537 – Installment Sales
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Internal Revenue Service. Topic No. 705, Installment Sales
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eCFR. 26 CFR 15a.453-1 – Installment Method Reporting for Sales of Real Property and Casual Sales of Personal Property
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Office of the Law Revision Counsel. 26 USC 453 – Installment Method
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Office of the Law Revision Counsel. 26 US Code 453A – Special Rules for Nondealers
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GovInfo. 26 USC 453A – Special Rules for Nondealers
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Office of the Law Revision Counsel. 26 USC 1274 – Determination of Issue Price in the Case of Certain Debt Instruments Issued for Property
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Office of the Law Revision Counsel. 26 US Code 483 – Interest on Certain Deferred Payments
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Internal Revenue Service. Rev. Rul. 2026-6 – Applicable Federal Rates
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Internal Revenue Service. Instructions for Form 8594
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Office of the Law Revision Counsel. 26 USC 197 – Amortization of Goodwill and Certain Other Intangibles
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Internal Revenue Service. About Form 6252, Installment Sale Income