Law Firm Partner Taxes: What Actually Changes When You Make Partner

A partnership pays no federal income tax itself. Its income, deductions, and credits pass through to the partners, who report their shares personally. The Schedule K-1 is the annual statement of your share, and under IRS guidance dating to 1969, a partner is not an employee of the partnership: no W-2, no withholding, no employer FICA match.

Partner pay usually has two layers. Guaranteed payments are the salary-like layer: fixed amounts paid for services regardless of firm profits, taxable to you and deductible by the firm. The distributive share is the ownership layer: your percentage of whatever profit remains, allocated under the partnership agreement. Both land on the K-1, and for a service partner both are generally subject to self-employment tax.

One feature of ownership catches every new partner: you are taxed on your allocated share whether or not the firm distributed the cash. Retained profits raise your capital account and basis, but the tax bill arrives on the full allocation. The visual in section five makes this concrete.

Most attorneys make partner mid-year, which means the transition year splits in half: W-2 wages with withholding through the promotion date, then K-1 income with nothing withheld after it. The withholding banked in the first half helps cover the year's liability, but it was calibrated to an associate salary, not a partner share, and the gap becomes the fourth-quarter surprise if nobody recalculates.

The checklist for the promotion quarter: start estimated payments immediately for the partner period; recompute the safe harbor using prior-year tax and the withholding already in; flip health and other benefits to the partner arrangement (premiums become guaranteed payments plus a 1040 deduction rather than a pre-tax payroll item); confirm the firm has taken you off W-2 payroll as of the effective date; and read the partnership agreement's capital, allocation, and expense reimbursement sections before signing, not after.

As an associate you paid 7.65% FICA and your employer matched it invisibly. As a partner both halves are yours, restyled as self-employment tax: 15.3% on net SE earnings up to the 2026 Social Security wage base of $184,500, then 2.9% Medicare with no cap, plus the 0.9% Additional Medicare Tax above $200,000 single or $250,000 joint. Half of the SE tax is deductible against income tax, and SE earnings are computed on 92.35% of the distributive share, which trims the sting slightly.

Attorneys sometimes ask about the "limited partner" exception, which excludes a limited partner's distributive share from SE tax. For working law partners the answer is: do not build on it. The Tax Court applies a functional analysis and has held that partners who actively generate the firm's income are subject to SE tax whatever their title, and although one circuit has disagreed with aspects of that approach and appeals were pending in others as of mid-2026, a practicing attorney is the least sympathetic possible claimant. The durable SE-tax levers are retirement deferral and, for some firms, entity design.

With no withholding, quarterly estimates carry the whole liability: April 15, June 15, September 15, and January 15. The safe harbors prevent penalties: pay 90% of the current year's tax, or 100% of last year's (110% if last year's AGI exceeded $150,000, which covers most partners). For a first full partner year, the 110% prior-year harbor is usually the calm choice: the number is fixed in April, and any shortfall against the real liability is settled penalty-free the following April.

Two refinements matter for partners. First, lumpy firms (contingency practices especially) can use the annualized income installment method so each quarter's payment reflects income actually earned to date. Second, state estimates run in parallel with their own rules, and a PTET election by the firm can shift part of the state burden to the entity, changing what the partner owes personally. The firm-level version of this machinery is on the law firm tax planning page, and the general mechanics are covered in our estimated taxes guide.

Your capital account is the ledger of your stake: buy-in contributions and allocated profits increase it, distributions and allocated losses decrease it. It is what the firm owes you, economically, at retirement or withdrawal. Alongside it runs tax basis, which starts with what you paid and contributed, moves with allocations and distributions, and includes your share of certain firm debt. Basis decides whether a distribution is taxable (generally not, until it exceeds basis) and whether allocated losses are currently deductible.

The buy-in funds the starting balance. Whether paid in cash, financed with a bank loan, or absorbed through reduced distributions, the buy-in is generally not deductible; it is an investment that becomes basis. Interest on a loan used to buy the partnership interest is generally allocable to the firm's business activity and deductible against that income. Before signing, get three numbers clear: the buy-in amount and schedule, how your capital account builds from retained profits, and what the agreement pays out (and when) if you leave.

A firm with offices in four states earns income in four states, and each partner owns a slice of all of it. Most states require nonresident partners to file returns on their allocated share of in-state income, allocated under each state's apportionment rules. A partner who has never set foot in the Chicago office can still owe Illinois tax on its profits.

Three mechanisms keep this manageable. Composite returns: the firm files one nonresident return covering consenting partners, paying at (often) the top rate in exchange for the partner skipping that state's filing. Withholding: many states require the firm to withhold on nonresident partners' shares, creating credits to claim. And the resident-state credit: your home state generally credits taxes paid to other states, so the multi-state total approximates the higher of the rates rather than the sum, though imperfectly. PTET elections layer on top, state by state, and can change which of these is optimal.

Employee benefits do not disappear at partnership; they change plumbing. Health premiums the firm pays for a partner are typically treated as guaranteed payments (income), offset by the self-employed health insurance deduction on your 1040, covering you, your spouse, and dependents. Retirement moves from "the 401(k) match" to the full partner-level system: elective deferrals of $24,500 for 2026 ($32,500 with the age-50 catch-up), profit-sharing allocations to the $72,000 defined-contribution cap, and, at many firms, a cash balance plan on top.

Partners also gain a deduction employees lost: unreimbursed partner expenses. Where the partnership agreement or firm policy requires partners to bear certain costs personally, home office, bar dues and licenses, client development, professional liability supplements, those can be deducted on Schedule E against partnership income, reducing income tax and SE tax both. The key word is "required": costs the firm would reimburse on request are generally not deductible if you simply do not ask.

Charitable giving, QBI positioning (law partners face the SSTB phase-out described on the planning page), and spouse employment strategies round out the personal-side toolkit; which ones matter depends on the numbers, which is what the consultation is for.