Setting up a profit-sharing plan takes five steps: decide the plan’s design rules, prepare a written plan document and trust agreement, formally adopt the plan through a board resolution and trust account, fund it within federal limits by your tax return deadline, and give eligible employees a Summary Plan Description. The plan is a defined contribution retirement arrangement qualified under 26 U.S.C. § 401(a),1Office of the Law Revision Counsel. 26 USC 401 – Qualified Pension, Profit-Sharing, and Stock Bonus Plans and once it exists, the Employee Retirement Income Security Act (ERISA) governs how you run it.2U.S. Department of Labor. ERISA You decide each year whether to contribute and how much; there is no fixed annual funding obligation.
Step 1: Decide the Plan’s Design
Three design choices lock in before anything else: who can participate, how contributions get split, and when employees own the money. Changing these later means plan amendments, extra IRS testing, and participant notices, so take the time now.
Eligibility
Federal law lets you require employees to reach age 21 and complete one year of service before they can join.3Office of the Law Revision Counsel. 26 USC 410 – Minimum Participation Standards You can set a lower threshold (immediate eligibility, a shorter waiting period) but you cannot exceed those statutory maximums. A year of service generally means a 12-month period in which the employee works at least 1,000 hours.
Allocation Formula
The simplest option is pro-rata: every participant gets the same percentage of their compensation. A participant earning $80,000 under a 10% contribution gets $8,000. Pro-rata formulas generally pass nondiscrimination requirements by design.
Age-weighted and cross-tested (new comparability) formulas direct more money toward older workers or specific employee groups, which often means owners. The trade-off is that these formulas require annual testing under IRC §401(a)(4) to prove they don’t improperly favor highly compensated employees (HCEs).4eCFR. 26 CFR 1.401(a)(4)-1 – Nondiscrimination Requirements of Section 401(a)(4) For 2026, an HCE is anyone who earned more than $160,000 from the employer during the prior year.5IRS.gov. 2026 Amounts Relating to Retirement Plans and IRAs, as Adjusted for Changes in Cost-of-Living
Vesting
Vesting controls when employer contributions become the employee’s permanently. (If the plan includes a 401(k) feature, employee deferrals are always 100% vested from day one; vesting applies only to employer money.) Two schedules dominate:
- Three-year cliff: 0% vested until three years of service, then 100% all at once.
- Six-year graded: 20% after two years of service, rising 20% per year until fully vested at six.
Faster vesting helps retention; slower vesting produces larger forfeitures when employees leave, and those forfeitures can be reallocated among remaining participants or used to offset future employer contributions.6Internal Revenue Service. Retirement Topics – Vesting
Step 2: Prepare the Plan Document and Trust
Every qualified plan needs a written plan instrument. For most small and mid-sized businesses, that means a pre-approved prototype or volume submitter plan document from a financial institution or third-party administrator (TPA). You get a standardized base document plus an adoption agreement where you fill in your choices on eligibility, allocation, vesting, and plan year. These documents come with an IRS opinion letter already covering their form.
Larger companies, or plans with unusual provisions, sometimes use an individually designed document drafted by an ERISA attorney. That route gives more flexibility but costs more and involves a longer IRS determination letter process.
Separately, ERISA requires all plan assets to be held in a trust for the exclusive benefit of participants and their beneficiaries.7Office of the Law Revision Counsel. 29 USC 1103 – Establishment of Trust A trust agreement names the trustees, defines their powers and duties, and creates a legal entity distinct from the business. The base document, adoption agreement, and trust agreement all have to be internally consistent. Errors in these documents can jeopardize the plan’s tax-qualified status.
Step 3: Formally Adopt the Plan
Adoption is the legal act that brings the plan into existence. Four concrete steps complete it:
- Pass a board resolution (or, for an LLC or sole proprietorship, document owner consent) authorizing the plan, and record it in your corporate minutes.
- Have an authorized officer sign the adoption agreement and trust document. The execution date establishes when the plan legally exists.
- Obtain a separate Employer Identification Number for the trust, distinct from the company’s EIN, so the IRS can track the trust’s activity independently.8Internal Revenue Service. Employer Identification Number
- Open a dedicated trust account at a financial institution to receive contributions. Plan assets must never be commingled with general business funds.
Retroactive Adoption
You no longer have to adopt the plan by December 31 to make it effective for that tax year. Under IRC §401(b)(2), as amended by the SECURE Act, an employer can adopt a new plan as late as the due date of its tax return, including extensions, and treat the plan as if it had been in place since the last day of the prior tax year.9Internal Revenue Service. Issue Snapshot – Deductibility of Employer Contributions to a 401(k) Plan Made After the End of the Tax Year For a calendar-year C corporation on extension, that means adopting as late as October 15 of the following year and still claiming the deduction on the prior year’s return.
Step 4: Fund the Plan Within the Limits
Three dollar limits control what can flow into a participant’s account each year.
- Annual additions limit under §415(c): employer contributions, employee deferrals, and forfeitures combined cannot exceed $72,000 per participant for 2026.
- Elective deferral limit under §402(g): if the plan includes a 401(k) feature, participants can defer up to $24,500 of pay in 2026. Participants age 50 and older can add a catch-up contribution of $8,000; those aged 60 through 63 qualify for an enhanced catch-up of $11,250 instead.
- Compensation cap under §401(a)(17): only the first $360,000 of a participant’s compensation counts when calculating contributions for 2026.
5IRS.gov. 2026 Amounts Relating to Retirement Plans and IRAs, as Adjusted for Changes in Cost-of-Living10Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500
On the employer side, total deductible contributions cannot exceed 25% of the aggregate compensation paid to all eligible participants during the year.11Internal Revenue Service. Retirement Topics – 401(k) and Profit-Sharing Plan Contribution Limits Contributions above the 25% ceiling are permitted but not deductible, and the excess may be subject to a 10% excise tax. For an owner trying to maximize personal savings, the interaction between the $72,000 per-person cap and the 25% aggregate deduction limit is where planning pays off.
The deadline for depositing contributions tracks the adoption deadline: the due date of the employer’s tax return, including extensions. A contribution made by that date is treated under IRC §404(a)(6) as if it was made on the last day of the preceding tax year for deduction purposes.12Office of the Law Revision Counsel. 26 USC 404 – Deduction for Contributions of an Employer to an Employees Trust or Annuity Plan and Compensation Under a Deferred-Payment Plan
Step 5: Give Employees a Summary Plan Description
ERISA requires you to tell eligible employees how the plan works through a Summary Plan Description (SPD), written clearly enough for the average participant to understand.13Office of the Law Revision Counsel. 29 USC 1022 – Summary Plan Description The SPD has to cover eligibility rules, the allocation formula, the vesting schedule, how and when benefits can be distributed, and the claims procedure for denied benefits.
For a new plan, you have 120 days from the plan’s effective date to deliver the SPD to participants. Any employee who joins the plan later must receive an SPD within 90 days of becoming a participant. Printed or electronic delivery both work, provided electronic delivery meets Department of Labor accessibility and privacy standards. Keep a distribution log showing who received the SPD and when, because sloppy recordkeeping is a common audit finding.
Keeping the Plan Compliant Each Year
Adoption is the beginning. Several annual obligations attach immediately and continue for every year the plan exists.
Form 5500
Every profit-sharing plan subject to ERISA files an annual return (Form 5500, or Form 5500-SF for plans with fewer than 100 participants) electronically through the EFAST2 system.14Internal Revenue Service. Form 5500 Corner It’s due by the last day of the seventh month after the plan year ends: July 31 for a calendar-year plan. Filing IRS Form 5558 before that date buys an automatic 2½-month extension to October 15.15Department of Labor. 2025 Instructions for Form 5500 Annual Return/Report of Employee Benefit Plan Penalties for late filing come from both the DOL (up to $250 per day with no statutory maximum)16eCFR. Civil Penalties Under Section 502(c)(2) and the IRS ($250 per day, capped at $150,000 per return).17Internal Revenue Service. Penalty Relief Program for Form 5500-EZ Late Filers
Top-Heavy Testing
Each year, check whether “key employees” hold more than 60% of total plan assets. Key employees include officers earning over $235,000 in 2026 and anyone owning more than 5% of the business.5IRS.gov. 2026 Amounts Relating to Retirement Plans and IRAs, as Adjusted for Changes in Cost-of-Living A plan that trips the 60% threshold is top-heavy, and the employer must make a minimum contribution of 3% of compensation for every non-key participant, whether or not the employer planned to contribute that year.18Internal Revenue Service. Is My 401(k) Top-Heavy Small businesses where the owner holds most of the balance trip this rule constantly. Budget for it.
Nondiscrimination Testing
The plan must satisfy IRC §401(a)(4) every year.4eCFR. 26 CFR 1.401(a)(4)-1 – Nondiscrimination Requirements of Section 401(a)(4) A straight pro-rata formula usually passes without issue. Age-weighted and cross-tested formulas require actual annual testing; failing it means either making corrective contributions to rank-and-file employees or refunding excess amounts to HCEs.
Summary Annual Report
After filing Form 5500, you have to give each participant a Summary Annual Report (SAR) within nine months after the close of the plan year. If you filed Form 5500 on extension, the SAR deadline shifts to two months after the extension period ends.19eCFR. 29 CFR 2520.104b-10 – Summary Annual Report The SAR is a short plain-language summary of the plan’s financial condition drawn from the most recent Form 5500.
Startup Costs Tax Credit
Small employers can offset much of the cost of launching a new plan through the startup costs tax credit under SECURE 2.0, which covers ordinary setup and administration expenses for the first three years of the plan.
- 50 or fewer employees: credit equals 100% of eligible startup costs, up to the greater of $500 or $250 per non-highly-compensated eligible participant, capped at $5,000.
- 51 to 100 employees: credit drops to 50% of eligible costs under the same dollar formula.
Employers with more than 100 employees who received at least $5,000 in compensation in the preceding year are not eligible.20Internal Revenue Service. Retirement Plans Startup Costs Tax Credit You claim the credit on Form 8881 against income tax liability. For a business with 20 non-HCE participants, the maximum works out to $5,000 per year for three years, which is often enough to cover TPA and recordkeeping fees during the plan’s early years.