How to Set Up a 401(k) for a Small Business, Step by Step

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How do I set up a 401(k) for my company? And how much of it lands on me?

Meet Ray. Ray is made up, though his situation comes from the plans we help set up. He owns a commercial landscaping company, twelve years in, fourteen people on payroll. Last month his lead foreman left for a competitor, and the exit conversation ended on a sentence Ray keeps coming back to. The other company has a 401(k).

So Ray searches how to set up a 401(k) for a small business, the same way you probably got here. The first result says he can start a plan in ten minutes. Fourteen people's retirement money, ten minutes? He closes the tab.

Setting up a 401(k) comes down to four design decisions: who gets in and when, whether the business contributes, how fast employees own that money, and what people are signed up for by default. Those choices decide whether the plan passes its yearly testing and how much the owners can put away, and a ten-minute signup page makes all four for you. Going through an advisor starts with one conversation that settles the design. From there the advisor lines up the recordkeeper, the administrator and payroll, and then stays on to run the plan year to year and be the person your employees ask about it.

Who does what once you start a plan

Four outfits touch a 401(k), and the ten-minute signup page picks all four on your behalf.

One job stays with Ray's company no matter who else is involved. The business is the plan sponsor, and it carries the fiduciary responsibility for running the plan in the employees' interest. Hiring good people for the pieces is part of meeting that responsibility, and the company still has to choose them and keep an eye on them afterward. We went through that in who does what on your 401(k).

What the first conversation settles

Four answers follow the plan for years, and a signup page fills them in for you. This is what Ray and his advisor work through, and the reason to work through it with somebody is that two of the four decide what Ray personally gets out of his own plan.

Who is eligible, and when. A plan can let people in on day one or make them wait up to a year. Ray's crew turns over in the first season, so he lets people defer their own money right away and waits a year before the company contributes anything.

Whether the business contributes. A match is optional, and this is the decision that costs owners the most when it gets made by default. If mostly higher earners end up saving, the plan fails its yearly nondiscrimination testing, and the fix is that the owners get part of their own contributions handed back as taxable income the following year. Ray would find that out in early 2028, after a year of thinking he was saving. A safe harbor design buys a pass on most of that testing in exchange for a set contribution: either 3% of pay to everyone eligible, or a match of 100% on the first 3% an employee puts in plus 50% on the next 2%, which comes to 4% of pay for someone deferring 5%.

How fast employees own the money. Traditional safe harbor money belongs to the employee immediately. Other employer contributions, like discretionary profit sharing, can vest over a few years, which is how a plan rewards people for staying.

What people are signed up for by default. Ray does not get a choice here. A 401(k) started today has to enroll employees automatically unless the business has 10 or fewer employees or has been around less than three years, and Ray's company is past both. The default rate starts between 3% and 10% of pay and steps up a point a year until it reaches at least 10%, capped at 15%. Employees can change it or opt out whenever they want.

Ray lands on a 4% safe harbor match with automatic enrollment at 5%, open to new hires right away, with the match starting after a year. It is his company and his plan, so he adopts it. What he wanted from the conversation was to see what each version cost the business and what it left him before he signed anything.

The five stages of setting up a plan

1. Design

We pull the company's census, meaning everyone's age, pay and hire date, and model what each design choice costs the business and what it does for the employees. Ray sees the price of the 3% nonelective next to the 4% match before he picks one.

2. Providers

The recordkeeper and the TPA get selected, and their fees get laid out in writing so the company can see what it pays and what comes out of employee accounts.

3. Documents

The TPA drafts the plan document and the company signs it. The signature date and the effective date are separate, and the effective date is what sets the plan year.

4. Payroll

Deferral codes get built in the payroll system and tested on a live run before any money moves. This is where launches tend to slip, so start early with whoever runs payroll.

5. Enrollment

Employees get the required notices, then a meeting where somebody explains what this is and answers questions. Then the first contribution comes out of a paycheck.

Who runs the plan after it launches

The setup finishes in a couple of months, and then the plan runs for as long as the company does. Every year it gets tested again, Form 5500 gets filed, notices go out, and the investment lineup needs somebody watching it.

We take the investment lineup on and monitor it. Choosing us and keeping an eye on us afterward stays with Ray's company, because that responsibility never transfers no matter who it hires. Everything else we coordinate, which means Ray is not the one chasing the recordkeeper when a contribution posts wrong, or finding out in July that a filing was due.

Once a year we go through the plan with him: who is participating, what it cost, whether a design built for fourteen people still fits a company that now has twenty.

And we are the person his crew asks. We run the enrollment meeting, and when somebody wants to know how the match works, what the default rate means, or what happens to their account if they leave, that question comes to us instead of to Ray from the cab of a truck. Those are the questions that decide whether a plan gets used by the people it was put in for, which is the reason Ray went looking in the first place.

The dates that decide what year you can start in

Three dates matter, and the first one has already gone by for this year.

A brand-new safe harbor plan has to run for at least three months in its first year, so a calendar-year plan had to be effective by October 1 to be safe harbor for 2026. That date has passed. If Ray wants the safe harbor design, and he does, January 1, 2027 is his start.

A plan that is not safe harbor can still be adopted for 2026. The business has until its tax filing deadline, extensions included, to sign a plan and treat it as adopted for the year that just ended, and employer contributions paid by that date can be deducted for that year. Employee deferrals only come out of paychecks after the plan exists, so a plan signed in December gives employees a couple of weeks of saving rather than a year of it. An owner with no employees is the exception and can make first-year deferrals as late as the due date of the individual return, without extensions.

What it costs to start one

Federal tax credits cover a good share of the startup cost for a business Ray's size, and for plans with 50 or fewer eligible employees they can reach $5,000 a year for three years, with more for adding automatic enrollment and for the money the business puts in for employees.

Ray signs at the end of November, in time for the safe harbor notice to reach his crew before the year starts. The match shows up on their January paychecks, and by then they have met the person who runs it.

ClearMind Capital's Workplace Retirement team, Austin Wolfe and Joe Anderson, sets up and runs 401(k) plans for businesses in Columbus, across Ohio and nationwide. Book a call with them and the first conversation does what Ray's did: your numbers, each design priced out, what it costs the business and what it leaves you, before you commit to anything.

Common questions

Can I set up a 401(k) for my small business myself?

You can sign up for one online, and for a business with no employees that is often fine. Once you have employees, the signup page is making your eligibility, contribution, vesting and default enrollment choices for you, and those choices decide whether the plan passes its yearly testing and how much the owners can put away. You are also signing up to run it yourself afterward, including the testing, the filings and the questions your employees bring you.

What does a 401(k) advisor do for a small business?

Before launch, an advisor models the design against your own payroll and tells you what each version costs the business and leaves the owners. At launch, the advisor lines up the recordkeeper, the administrator and payroll so the owner is not project-managing it. After that it is ongoing: monitoring the investment lineup, reviewing the plan with you every year, and being the person your employees go to with questions about their money.

How long does it take to set up a 401(k)?

Plan on six to eight weeks before your target effective date. Payroll integration is the step that stretches timelines, because deferral codes have to be built and tested on a live run before money moves.

Do I have to offer a match?

No. A plan can take employee money and nothing from the business. The catch is nondiscrimination testing: if mostly higher earners participate, the plan fails and the owners get part of their contributions refunded to them as taxable income. A safe harbor contribution buys a pass on most of that testing, which is why so many small plans use one.

What does a 401(k) cost a small business?

Setup and yearly administration, plus whatever the business decides to contribute, offset by the federal credits. We put the costs and the credits next to each other in what a 401(k) really costs a small business, and the case for offering one at all in should my Ohio business start a 401(k). If you already have a plan and want to know what it is costing your people, the ClearMind 401(k) Scorecard™ grades it from public filings.

What can my employees put in once the plan is running?

For 2026, an employee can defer up to $24,500 of their own pay, plus $8,000 more at age 50 and over, or $11,250 at ages 60 through 63. Employee and employer money together can reach $72,000 a year for one person, with the catch-up on top of that. These limits are indexed, so they move most years.

Written byAustin Wolfe & Joe AndersonClearMind Capital | Workplace RetirementView bio →

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