Consulting Business Entity Structure: The LLC, the S Election, and the 'Consulting' Classification That Caps the QBI Deduction

Consultants have the clearest specified-service classification and the least room for a low S corporation salary, and the entity analysis has to hold both. The classification, settled: the specified service trades or businesses include "consulting" — defined in the regulations as the provision of professional advice and counsel to clients to assist them in achieving goals and solving problems, including advice on strategy, operations, finance, and similar matters, and excluding training and educational courses and sales-related services that aren't advice — so management, strategy, operations, IT, and financial consulting are SSTBs by definition, the QBI deduction phases out above the taxable-income threshold (indexed; the range widened to US$75,000/US$150,000 and made permanent by the 2025 legislation) and disappears above the range, and the consultant's planning runs on taxable income against the threshold (the coaching entity guide covers the same mechanics from the adjacent trade); the exclusions matter at the edges — a consulting firm that also delivers training programs or implements systems (implementation and staffing are not advice) has a mixed character, the de minimis rule (SSTB receipts under 10% of the total below US$25 million of gross receipts; 5% above) rarely rescues a consulting-dominant firm, and the separate-trade-or-business analysis can classify a genuinely separate implementation or training line on its own. The structures (the LLC cost guide): a sole proprietorship or single-member LLC on Schedule C — self-employment tax on all net profit (15.3% on 92.35% up to the wage base, 2.9% above, plus the Additional Medicare Tax above US$200,000), no payroll, one return; an LLC electing S status — a reasonable salary through payroll, distributions free of payroll tax, Form 1120-S; a multi-member LLC taxed as a partnership (partners' guaranteed payments and distributive shares, both subject to self-employment tax for active partners); an LLC or corporation electing S status with multiple shareholders (salaries by role, distributions strictly by ownership under the single-class-of-stock rule); and the C corporation (considered for a firm retaining earnings or planning an exit through a stock sale — the succession guide). The reasonable-salary question — the consultant's constraint: the IRS expects the owner to be paid what a comparable employee would earn for the services performed, and for a consultant the comparison is direct — what an employed consultant of the owner's seniority earns at a consulting firm or in industry (published compensation data is abundant for consultants: the industry surveys, the large firms' published bands, the state's workforce data for management analysts) — so a solo consultant billing US$300,000 whose comparable employed compensation is US$180,000 has a defensible salary of US$180,000 and a distribution portion of US$120,000, not a US$60,000 salary and US$240,000 of distributions; a consulting practice's revenue is the owner's personal services almost entirely, and the reasonable salary is a large share of the profit — the structural reason the S election saves consultants less than it saves a contractor with a crew, and the reason the salary is documented against the market data rather than set by what the owner would like to distribute. The saving, honestly: payroll tax avoided on the distribution portion — for a consultant whose salary reaches the Social Security wage base, the saving on distributions above it is 2.9% (Medicare) plus the 0.9% Additional Medicare Tax avoided — 3.8% — not the 15.3% headline; a consultant with a US$180,000 salary and US$120,000 of distributions saves about US$4,500 (3.8% of US$120,000, the salary having exhausted the wage base); a consultant with a US$90,000 salary (below the wage base) and US$60,000 of distributions saves about US$9,000 (15.3% on the portion up to the wage base) — the saving is larger for consultants whose salary sits below the wage base, which is also where the salary is more likely to be challenged as too low. The election's costs: the 1120-S, a payroll (new, for a solo consultant), basis tracking, the state's S corporation layer, and — for a consultant with a home office — the accountable-plan reimbursement that replaces Form 8829. The QBI interaction, by band: below the threshold, the QBI deduction is full under either structure and the salary's removal from the QBI base costs 20% of the salary in deduction (a real cost — a US$150,000 salary is US$30,000 of deduction, worth several thousand at the bracket), which for a solo consultant below the threshold often outweighs a 3.8%-above-the-wage-base payroll-tax saving; in the phase-out range, the QBI deduction is partial and the threshold strategy (the consulting retirement guide — a SEP, Solo 401(k), or defined benefit contribution that pulls taxable income below the threshold, alongside the practice's deductions) is worth more than the election; above the range, no QBI deduction under any structure, and the election is pure payroll-tax arithmetic — small above the wage base, but positive, and the S corporation's other benefits (the salary's Social Security record, the cleaner separation of the business, the retirement plan's W-2 basis) carry the decision. The bands, then: a solo consultant netting under about US$150,000 — often Schedule C, because the reasonable salary is most of the profit, the saving above the wage base is 3.8%, and the QBI cost of the salary below the threshold is real; US$150,000 to the range — the worksheet, with the threshold strategy run alongside; above the range with profit well above the reasonable salary — the S election on payroll-tax arithmetic plus the structural benefits, with the salary documented against the market. The boutique with a bench: a firm with W-2 consultants (the classification guide — the bench that works only for the firm is on payroll) has W-2 wages beyond the owner's salary — the payroll exists (the S election's incremental cost falls), the wage-and-property limitation is satisfied by the bench's wages (relevant for a non-SSTB line above the threshold; irrelevant for the SSTB line above the range), and the owner's salary is a managing partner's or practice leader's market compensation. The multi-partner firm: partnership taxation (guaranteed payments by production, special allocations, self-employment tax on all active partners' full shares — the flexibility multi-partner firms want) versus S corporation taxation (salaries by production, distributions strictly by ownership — the constraint that makes unequal producers subsidize each other unless ownership tracks production — the chiropractic entity guide's multi-doctor point); most multi-partner consulting firms are partnerships (LLCs or LLPs) for the compensation flexibility, and the ones that elect S status realign ownership to production or accept the salary differential as the equalizer. The liability layer: the LLC protects the consultant from the business's contractual liabilities (a client's claim over an engagement's outcome) but not from the consultant's own professional negligence — professional liability insurance (errors and omissions) covers the advice (the consulting insurance guide); the LLC and the insurance are both required. The exit consideration: a consulting firm's sale is usually an asset sale with personal goodwill as the main component (the succession guide) — a C corporation complicates it (double taxation on the corporation's goodwill; the personal goodwill sold directly by the owner as the workaround), which is one reason consulting firms stay pass-through. The annual re-run: profit, the revenue mix (more implementation, more training — the classification edges), the threshold's indexing, the retirement contribution, and the salary against updated market data — revisited each January.

Key takeaways

• Consulting is an SSTB by name — advice and counsel to achieve goals and solve problems; training and implementation are excluded — so the QBI deduction phases out above the threshold under any entity, and the consultant's planning runs on taxable income against the line.
• The reasonable salary is most of the profit — an employed consultant of the owner's seniority is the direct comparison, with abundant published data — leaving a smaller distribution portion than other trades'.
• The saving above the wage base is 3.8%, not 15.3% — a consultant whose salary exhausts the wage base saves Medicare and the Additional Medicare Tax on distributions only; the larger saving belongs to consultants with salaries below the wage base, who are also more exposed on reasonableness.
• Below the threshold, the salary's QBI cost (20% of the salary) often outweighs the saving; in the range, the retirement threshold strategy beats the election; above the range, the election is positive on payroll tax plus structural benefits.
• Multi-partner firms are usually partnerships for compensation flexibility (guaranteed payments by production); the S election forces distributions by ownership.
• The LLC covers contract liability, not negligence — errors and omissions insurance covers the advice; pass-through structure keeps the exit's personal goodwill single-taxed.

The consultant's entity worksheet

Classification (SSTB; any training or implementation line and the de minimis or separate-business analysis). Taxable income against the threshold and range. Reasonable salary (employed-consultant market data at the owner's seniority — documented). Distribution portion; payroll tax saved at the applicable rate (15.3% below the wage base; 3.8% above). Election costs (1120-S, new payroll, basis tracking, state layer, accountable plan). QBI under each structure by band. Threshold strategy (retirement room). Multi-partner: compensation design under partnership vs S corporation rules. Net result. Fifteen minutes each January — and the salary line, documented against the market, is the one the S corporation lives or dies on.

Worked example

Three consultants. One: a solo operations consultant netting US$140,000, married, household taxable income below the threshold. Reasonable salary (an employed senior consultant in her market): about US$125,000 — most of the profit. The S election: a US$15,000 distribution saving about US$2,300 (below the wage base), against a new payroll, the 1120-S, the state fee, and US$25,000 of QBI base lost to the salary (worth several thousand at her bracket). Net: negative — Schedule C, with a single-member LLC for contract liability and E&O insurance for the advice. Two: a solo strategy consultant netting US$310,000, single, taxable income above the SSTB range — no QBI deduction under any structure. Reasonable salary (an employed principal-level consultant): about US$200,000, above the wage base. The S election: US$110,000 of distributions saving 3.8% — about US$4,200 — against the 1120-S and a new payroll; marginally positive on tax, and elected for the structural benefits (a defined benefit plan on the W-2 salary — the retirement guide; the clean separation; the eventual sale's structure). Three: a boutique with four W-2 consultants and two partners netting US$280,000 each, taxable income above the range, unequal production (US$1.1 million and US$700,000 in billings). Partnership: guaranteed payments by production, self-employment tax on both shares, the compensation design the partners want. S corporation: salaries by production (US$220,000 and US$160,000 as practice leaders), but distributions by their 50/50 ownership — the top producer subsidizes the other unless ownership is realigned; they stay a partnership, and the bench's W-2 wages support the QBI limitation on the small training line they run as a separate business. Three consultants, one classification, three entity answers — decided by taxable income, the wage base, and the compensation design.

Official sources

The IRS states that "an SSTB is a trade or business involving the performance of services in the fields of health, law, accounting, actuarial science, performing arts, consulting, athletics, financial services, investing and investment management, trading or dealing in certain assets, or any trade or business where the principal asset is the reputation or skill of one or more of its employees or owners," and that above the taxable-income threshold "the QBI component will be limited by the amount of W-2 wages paid by the qualified trade or business and the UBIA of qualified property." — Internal Revenue Service, Section 199A qualified business income deduction FAQs, https://www.irs.gov/newsroom/tax-cuts-and-jobs-act-provision-11011-section-199a-qualified-business-income-deduction-faqs

The IRS states that "S corporations are corporations that elect to pass corporate income, losses, deductions, and credits through to their shareholders for federal tax purposes." Shareholder-employees who perform services must be paid reasonable compensation as wages before distributions, and the election is made on Form 2553. — Internal Revenue Service, S corporations, https://www.irs.gov/businesses/small-businesses-self-employed/s-corporations

Practitioner note

Consulting is the specified service trade the regulations name, and the consultant's S election arithmetic is the least generous in this series: the reasonable salary is most of the profit because the comparison to an employed consultant is direct and documented, and the saving on distributions above the wage base is 3.8%, not the headline rate. Our worksheet runs the classification, the band, and the salary against market data every January — and below the threshold the salary's QBI cost usually settles it for Schedule C, while above the range the election earns its keep on the structural benefits more than the tax.

See also: For related guidance, see the consulting deductions guide; and browse every small business tax guide, by situation.

Next step

Fairlight Accounting is a cross-border accounting and tax practice with a U.S. Tax Desk and a Canadian Tax Desk. Our U.S. Tax Desk handles entity structure for consulting businesses — the specified-service classification with training and implementation edges, the S election worksheet with market-documented reasonable compensation and wage-base-aware savings, the QBI analysis by band with the retirement threshold strategy, and multi-partner compensation design. See pricing or book a call.