What state taxes are triggered when a corporation buys a Washington LLC?

Why the form of the purchase decides the Washington answer

Washington's excise taxes are imposed on persons, and the definition of "person" names the "limited liability company" (RCW 82.04.030). A registered LLC holds its own unified business identifier and its own tax accounts (WAC 458-20-101(6)). When a corporation buys every membership interest, the taxpayer does not change: the LLC still owns its equipment, inventory, vehicles, real property and contracts, and still owes whatever it owed before closing. What changes is who owns the LLC.

The federal income tax may see the deal differently: a purchase of all the interests of an LLC classified as a partnership or disregarded entity is generally treated federally as a purchase of its assets, which is why a buyer can often obtain a basis step-up without papering an asset deal. Washington's excise taxes follow the legal form. No tangible personal property passes from seller to buyer, so there is no retail sale to tax; no deed passes either, which is the gap the controlling interest rules in chapter 82.45 RCW close.

The registration rule draws the same line: a "change in ownership" does not occur on "[t]he sale of all or part of the common stock of a corporation" (WAC 458-20-101(11)(b)). The rule does not mention a change in an LLC's members; the stock-sale example is the closer analogy, since the LLC also continues as the same registered person, but the rule does not say so in terms.

Real estate excise tax on the controlling interest

The real estate excise tax defines "sale" to include "the transfer or acquisition within any 36 month period of a controlling interest in any entity" with an interest in Washington real property, for valuable consideration (RCW 82.45.010(2)(a)). For an entity other than a corporation, a controlling interest is 50 percent or more of its capital, profits or beneficial interest (RCW 82.45.033(1)(b)). A buyer that takes 40 percent now and the balance within 36 months is tested on the total, and "all acquisitions of persons acting in concert must be aggregated" (RCW 82.45.010(2)(c); WAC 458-61A-101(5)). The Department may also "disregard the form of the transaction or series of transactions" arranged to reduce the graduated tax (WAC 458-61A-1001(8)). The library's article on controlling interest transfer taxes compares Washington's threshold, lookback period and measure with those of other states.

The measure. The selling price is the value of the entity's Washington real property, not the deal price (RCW 82.45.030(2)). The Department's rule illustrates it with an entity holding $250,000 of real property, $130,000 of tangible personal property and $55,000 of intangibles, where the taxable selling price is "the true and fair value of the real property owned by the corporation, or $250,000" (WAC 458-61A-101(4)(c)(ii)). Where that value cannot reasonably be determined, the rule allows a fair market value appraisal or an allocation of assets under Internal Revenue Code section 1060, and failing both, the market value assessment on the county rolls (WAC 458-61A-101(4)(a), (b); RCW 82.45.030(4)).

The rates. The state rate is graduated by portion of the selling price (RCW 82.45.060), and for a controlling interest transfer the rate is set by "the true and fair value of the real property owned by the entity at the time the controlling interest is transferred," taken as a whole (WAC 458-61A-1001(6)(b)). The Department's published thresholds, in effect since January 1, 2023, apply 1.1 percent to the first $525,000, 1.28 percent above $525,000 through $1,525,000, 2.75 percent above $1,525,000 through $3,025,000, and 3 percent above $3,025,000. The Department has published adjusted thresholds effective January 1, 2027 of $551,000, $1,551,000 and $3,051,000 at the same rates, so a closing that slips into January carries a slightly lower tax on the same property. Local real estate excise tax applies on top: RCW 82.46.010 reaches "persons who are taxable by the state under chapter 82.45 RCW," and the Department's instructions state that the local rate "must be calculated and added to the graduated state rate."

Who pays. The tax "is the obligation of the seller" (RCW 82.45.080(1)), and for a controlling interest "the seller of the interest is generally liable for the tax" (WAC 458-61A-101(7)), but the buyer is exposed too. For an entity that is not a corporation, the Department may enforce the seller's obligation against the entity or against the person or persons who "transferred or acquired the controlling interest" (RCW 82.45.033(2)(b); WAC 458-61A-101(7)(a)(ii)), and unpaid tax is "a specific lien on each parcel of real property in this state owned by an entity" whose control changed, enforceable as a mortgage foreclosure (WAC 458-61A-101(7)(b)). If the tax is not received when due, the transferee is also personally liable for the tax and interest unless an instrument of sale is recorded (RCW 82.45.100(3)), and in a controlling interest transfer nothing is recorded. After closing, the entity the Department can pursue belongs to the buyer, and a seller's covenant to pay protects the buyer only as far as the seller pays.

Reporting, penalties and limitations. Where no instrument is recorded, "the sale must be reported to the department of revenue within five days from the sale date," on forms "signed or electronically signed by both the transferor and the transferee" and accompanied by payment (RCW 82.45.090(2)). Interest runs from the date of sale if the tax is not paid within one month, and the penalty is 5, 10 and 20 percent of the tax at one, two and three months, "collectible from the seller only" (RCW 82.45.100(1), (2)). The rule's own example says a buyer "is not relieved of personal liability for the tax, interest, or penalties" if the Department cannot collect from the sellers (WAC 458-61A-101(8)(iv)(B)), which sits uneasily with the statute's seller-only penalty language; the statute controls. The four-year limit on assessments does not apply where the transferor or transferee fails to report under RCW 82.45.090(2) (RCW 82.45.100(5)(c)), so an unreported controlling interest transfer stays open.

A second report runs through the Secretary of State. RCW 43.07.390 requires entities that file an annual report and own Washington real property to disclose transfers of a controlling interest, or of "an interest that amounts to at least one-third of a controlling interest," and grants of options to acquire them. An organization that fails to report a transfer that produces a controlling interest sale "is subject to the provisions of RCW 82.45.100 as well as the evasion penalty in RCW 82.32.090(7)" (RCW 82.45.220), a penalty of "50 percent of the additional tax found to be due" (RCW 82.32.090(7)). That duty is the LLC's, and so, after closing, the buyer's.

An LLC that only leases. Chapter 82.45 defines real property to include "improvements constructed upon leased land" (RCW 82.45.032(1)), and the Department taxes a direct transfer of a leasehold "to the extent the transfer includes any improvement constructed on leased land" (WAC 458-61A-106(1)(b)). The Department reads the controlling interest rules the same way: on a stock sale of a tenant whose only Washington real property was leasehold improvements its leases did not require it to remove, tax was due on the value of those improvements (Det. No. 16-0111, 36 WTD 103 (2017)). Build-out in leased space is part of the measure unless the lease requires its removal.

The LLC's B&O, sales and use tax: no successor, and no clearance

Washington's successor statute is built for the transfer of a business's assets. A successor is a person who acquires a business from a taxpayer that quits, sells out, exchanges or disposes of it, where the transfer is "in bulk and not in the ordinary course of the taxpayer's business" and covers "more than fifty percent of the fair market value of either the (i) tangible assets or (ii) intangible assets," or is "[a] surviving corporation of a statutory merger" (RCW 82.04.180(1)). The Department's rule tracks those categories, adds the surety of a defaulting contractor, and lists no others (WAC 458-20-216(2)(a)). A purchase of membership interests transfers no asset of the LLC, so the buyer does not fit the definition, and the LLC remains the taxpayer for every period before closing.

That is not protection. The LLC's unpaid B&O tax, its retail sales tax whether or not collected, the use tax on its own untaxed purchases, and the interest and penalties on all of them remain the LLC's liabilities, and the buyer bears them through ownership. The successor machinery does not reach the deal: the duty to withhold until the seller produces "a certificate from the department that no tax is due," and the rule that a successor is not liable where it gives written notice and no assessment issues within six months, are written for successors (RCW 82.32.140(2), (4); WAC 458-20-216(5), (6)). Nor does the successor's exclusion from "interest or penalties associated with the taxpayer's tax liability" (WAC 458-20-216(5)(a)) apply, because the LLC owes them as the taxpayer.

The limitations period is the LLC's own. The four-year assessment limit does not apply "against a taxpayer who has not registered as required by this chapter," on a showing of fraud or material misrepresentation, or under a signed waiver (RCW 82.32.050(4)). A registered LLC's exposure generally runs back four years plus the current year; an LLC that did business in Washington without registering carries every unregistered year. For retail sales tax collected and not remitted, the Department's voluntary disclosure program applies "an unlimited look back period." That program's full benefits go only to a business with no active registration or reported taxes, and no enforcement contact, in the prior four years plus the current year, so a registered LLC with underreported periods is usually outside them; the pre-closing choices are amended returns or a holdback sized to the diligence findings.

A post-closing merger of the LLC into the buyer is a separate event that makes the buyer "[a] surviving corporation of a statutory merger" and a successor by statute (RCW 82.04.180(1)(b)). A transfer of the LLC's assets up to its new parent is outside retail sales tax "to the extent the transfer is accomplished through an adjustment of the beneficial interest in the business" (WAC 458-20-106), but whether it makes the parent a successor under RCW 82.04.180(1)(a) is not addressed in the rule's examples, and a later deed of the real property is a new transfer tested under the exclusions in RCW 82.45.010(3).

The buyer's registration and the LLC's own accounts

The LLC's unified business identifier, Department account, filing frequency and license endorsements stay with the entity. Even without a change in ownership, "the completion of a new business license application may be required to reflect the changes in the registered account" (WAC 458-20-101(11)(c)), and the application carries the governing persons' names and contact information (WAC 458-20-101(7)(c)), so the LLC's record is brought current after closing.

The buyer's own registration turns on its own activity. Washington has no corporate income tax, and a person engaged in a business activity on which the Department administers a tax registers unless the small-business conditions apply (WAC 458-20-101(2), (5)). Holding the interests is an investment, and amounts a parent receives "as dividends or distributions from the capital account" from its subsidiary entities are deductible from the B&O measure (RCW 82.04.4281(1)(b)), though the statute as read does not define "subsidiary entity." Outside Washington, an LLC disregarded for federal purposes generally passes its activity in income tax states through to its corporate owner, so the buyer can acquire filing obligations elsewhere on the closing date.

Property tax does not reset: "[a]ll taxable real property within a county must be revalued annually" (RCW 84.41.030), and no change-in-ownership reassessment applies.

The sellers may owe tax of their own. An individual seller domiciled in Washington can owe the capital gains excise tax on the interests, but gain "directly attributable" to real estate the entity owns directly is exempt, measured by that real estate's fair market value less basis, times the percentage sold, and the Department is not bound by the parties' appraisal or section 1060 figures where they do not reflect fair market value (RCW 82.87.050(2)). The same allocation therefore drives the excise tax on the controlling interest and the sellers' exemption. The library's article on whether Washington taxes capital gains covers that tax.

The asset-purchase alternative

Recasting the deal as a purchase of the LLC's assets moves each tax.

Real estate excise tax applies to the deed in the ordinary way (RCW 82.45.010(1)), measured by the selling price of the property conveyed (RCW 82.45.030(1)) and paid to the county treasurer before recording (RCW 82.45.090(1)).

Retail sales tax applies to the LLC's sale of its furniture, fixtures and equipment. The casual sale exemption does not reach a sale "made by a person who is engaged in a business activity taxable under chapters 82.04 or 82.16 RCW" and gives no exemption from use tax (RCW 82.08.0251; WAC 458-20-106), so if the seller does not collect, the buyer owes use tax. Inventory passes at wholesale only if the seller takes a copy of the buyer's reseller permit, since "[a]ll sales are treated as retail sales unless the seller takes from the buyer a copy of a reseller permit" (WAC 458-20-102(5)), which puts the buyer's registration before closing. Vehicle use tax is collected "at the time an applicant applies for transfer of certificate of title" unless the applicant shows the tax was paid (RCW 82.12.045).

Successor liability attaches to a buyer of more than half the value of the tangible or intangible assets (RCW 82.04.180(1)(a)), but with the protections the equity buyer lacks: withholding against a certificate, written notice followed by six months without an assessment, and liability for tax without the seller's interest and penalties (RCW 82.32.140; WAC 458-20-216(5), (6)). The library's article on whether an asset purchase triggers sales tax and successor liability covers those mechanics across several states. The sale of a business is also a change in ownership (WAC 458-20-101(11)(a)(i)), so the buyer starts under its own accounts.

The trade, in Washington terms: the membership-interest purchase avoids retail sales tax on the equipment and inherits the LLC's whole tax history with no clearance route; the asset purchase pays that tax and leaves the history behind, under a successor statute that offers one.

A worked example

A corporation based in another state buys all the membership interests of a Washington LLC that operates three veterinary clinics, for $9 million at a single closing in November 2026. The LLC owns one clinic building, appraised at $2.4 million, and leases the other two premises, where it built out exam and surgery rooms. It also holds $1.1 million of equipment and furniture and an inventory of pet food and supplies for sale.

The acquisition is a controlling interest transfer. The state tax is measured on the $2.4 million building, not the $9 million price: $5,775.00 on the first $525,000, $12,800.00 on the next $1,000,000 and $24,062.50 on the remaining $875,000, or $42,637.50, plus the local rate at the building's location. Had the closing slipped to January 2027, the same building would carry $42,208.50 under the adjusted thresholds. The build-out in the two leased clinics is also real property unless the leases require its removal, and its value is added to the measure on top of these figures. Both parties sign the five-day return, the LLC reports the transfer to the Secretary of State, and the buyer is answerable for the tax and interest if the seller does not pay. No retail sales tax applies to the equipment or the inventory.

Diligence shows that one clinic's point-of-sale system charged no retail sales tax on product sales for two years. That liability, with interest and penalties, belongs to the LLC and sits inside the four-year window. No certificate or notice procedure is available to the buyer, so its protection is amended returns before closing or a holdback and indemnity sized to the finding. In an asset purchase, by contrast, the $1.1 million of equipment would bear retail sales tax at the clinics' location rates, and the buyer could withhold against a certificate or give written notice and take the six-month protection.

Practice notes

The sound sequence starts with the LLC's real property: every owned parcel, every ground lease and every improvement the LLC built on leased premises, valued as of the expected closing date. The allocation in the purchase agreement then serves three purposes at once: the measure of the excise tax on the controlling interest, the sellers' real estate exemption from the capital gains excise tax where they are Washington individuals, and the federal allocation. The closing checklist carries the five-day return signed by both parties and the Secretary of State disclosure. The LLC's history is diligenced as the buyer's own, because it will be: B&O classifications, retail sales tax by location, use tax on untaxed purchases and any period before registration, with amended returns or a holdback for what diligence finds. A buyer weighing an asset deal for its federal benefit prices the retail sales tax on the equipment against the successor statute's clearance route, after testing whether the interest purchase already delivers that benefit. G&G State Tax Group provides Washington state and local tax diligence on entity acquisitions, including real estate excise tax on controlling interest transfers and pre-closing sales and use tax review, alongside its state and local tax practice.