If you’re a small business owner with a 401(k) plan, you may have run into a frustrating roadblock: You and your highly compensated employees (HCEs) can’t always contribute as much as you’d like. This is thanks to IRS nondiscrimination testing rules that compare what owners and top earners put in against the rest of the team.
A safe harbor 401(k) can solve that problem. By committing to certain employer contributions, you bypass those testing limits, allowing owners and HCEs to maximize their savings.
Although safe harbor plans can be a powerful tool, they’re not a one-size-fits-all solution. Before you commit, it’s important to understand how they work, what they cost, and the myths that often trip up business owners.
What is a Safe Harbor 401(k)?
A safe harbor 401(k) is a retirement plan that automatically satisfies the IRS nondiscrimination tests. In a regular 401(k), if rank-and-file employees don’t contribute much, owners and HCEs may get capped or even have part of their contributions refunded. With a safe harbor plan, the employer agrees to make certain contributions to employees’ accounts, and in exchange, the IRS waives those tests.
This means business owners and other HCEs can contribute the maximum allowed each year without worrying about being limited by the rest of the team’s participation. In 2025, the 401(k) contribution limit is $23,500 (or $31,000 if you’re over 50, or $34,750 if you're between 60 and 63). For many owners, this makes safe harbor the difference between hitting their retirement savings goals or falling short.
What are the Safe Harbor 401(k) Contribution Options?
With a safe harbor plan, employers are required to make contributions to employees’ accounts. These contributions immediately vest, meaning employees own them outright. Employers can choose from three main safe harbor 401(k) contribution designs:
- Non-elective contribution: At least 3% of pay contributed for every eligible employee, whether or not they contribute
- Basic match: 100% match on the first 3% employees contribute, plus 50% on the next 2%
- Enhanced match: 100% match up to 4% (or more generous if desired)
Each option balances cost and employee appeal differently. A company looking to encourage participation may prefer one of the safe harbor 401(k) match options, while a company with low participation might lean toward the non-elective contribution.
Timing & Implementation Considerations
For new 401(k) plans, safe harbor provisions must usually be established by October 1, and employees must be notified at least 30 days prior.
If you’re converting an existing 401(k) to a safe harbor plan for the new calendar year, you have until December 31 to add the safe harbor provision and must notify employees of the change by December 1.
Don’t worry, you’re not stuck with a safe harbor plan forever. With few exceptions, you must keep the safe harbor for the full plan year once you adopt it. However, you can revisit the decision each year. With the proper notice, employers can also remove the safe harbor provision if it no longer fits the business.
Wondering if it’s the right time to add or remove your safe harbor plan? Consider:
- Adding when owners or HCEs are consistently limited in their contributions, or when you want to strengthen your benefit package
- Removing when employee participation improves enough that traditional 401(k) testing isn’t a concern, or if employer contributions no longer fit your cash flow
What Will It Cost—and What Do I Get Back?
So, how much will employer contributions really cost you? It depends on your workforce size, compensation, and the safe harbor option you choose. Here’s a simple example of a company with 10 employees:
Scenario 1: Nonelective contribution (3% for all eligible employees)
- For 10 employees earning $50,000 each, the contribution is $1,500 per employee.
- Total annual employer cost: $15,000
Scenario 2: Basic match (100% up to 3% + 50% on the next 2%)
- If employees contribute at least 5% of pay, the employer’s match works out to 4% of $50,000, or $2,000 per employee.
- Total annual employer cost: $20,000
Scenario 3: Enhanced match (100% up to 4%)
- Contribution is also 4% of $50,000, or $2,000 per employee.
- Total annual employer cost: $20,000
In this example, required contributions would fall between $15,000 and $20,000 per year, depending on the plan design.
Fortunately, employer contributions are tax-deductible, lowering your taxable income. That means a $20,000 contribution also creates a $20,000 deduction.
And if you’re concerned about a lean year, remember that you’re not locked into the safe harbor plan forever. While contributions are required annually, you can revisit the plan design annually to ensure it still fits your budget and company needs.
Safe Harbor 401(k) Benefits Beyond Compliance
In addition to satisfying nondiscrimination testing requirements, a safe harbor plan supports:
- Recruiting and retention: Guaranteed contributions make your benefits package stronger and more competitive.
- Owner peace of mind: You won’t face the headache of failed testing or contribution refunds.
- Stability: Predictable rules year after year simplify retirement planning for everyone.
Safe Harbor Plan Myths & Misconceptions
There are several myths and misconceptions surrounding safe harbor 401(k) plans, so let’s address three of the most common ones that we hear.
“Safe harbor plans are only for big companies.” Not true—in fact, many small businesses find safe harbor the easiest way to let owners and employees save more. As of year-end 2024, 30% of all defined contribution plans administered by Vanguard had adopted a safe harbor design, according to their 2025 How America Saves report.
“A safe harbor 401(k) will be too expensive for my business.” Costs vary, and tax deductions often offset much of the expense.
“Once I add it, I can’t get rid of it.” This is also false! Again, you can change the plan design or drop the safe harbor provision with proper notice.
Key Considerations Before Establishing a Safe Harbor 401(k)
Before committing to a safe harbor plan, owners and leadership should ask themselves:
- Do you have a steady enough cash flow to make annual contributions? Safe harbor requires employer contributions every year, no matter how employees contribute. If your revenue fluctuates, you’ll want to ensure the commitment won’t strain your budget in slower seasons.
- How big is your team, and how much turnover do you have? The more employees you have—and the higher the turnover—the more your safe harbor contributions could add up. Understanding your workforce makeup helps avoid surprises in employer costs.
- Do you want to use the plan as a recruiting and retention tool? Safe harbor contributions are guaranteed, which can make your benefits package much more attractive. If hiring and keeping good employees is a challenge, this can be a valuable differentiator.
- Would another design, like profit-sharing or a new comparability plan, achieve the same goals at a lower cost? Safe harbor is one of several plan structures available. Sometimes other designs can allow owners to maximize contributions while giving you more flexibility in how employer dollars are allocated.
Is a Safe Harbor Plan Right for Your Business?
A safe harbor 401(k) can be a powerful way for business owners and highly compensated employees to save more for retirement, while also strengthening employee benefits. But it’s not the right answer for every business. Timing, cash flow, and long-term goals all play a role in whether it makes sense.
If you have a steady cash flow and want a plan that doubles as a strong recruiting and retention tool, a safe harbor plan may be an excellent fit. But if your workforce is large or highly transient, or if flexibility is more important than guaranteed contributions, you may want to explore alternatives like profit-sharing or new comparability plans.
Reach out to FSRP today to explore whether a safe harbor 401(k) is the right fit for your business today and in the years ahead.
Securities and advisory services offered through Commonwealth Financial Network, Member FINRA/SIPC, a Registered Investment Adviser. Financial Strategies Retirement Partners (FSRP) is a Registered Investment Adviser. Financial planning services offered by FSRP are separate and unrelated to Commonwealth. FSRP does not provide legal or tax advice. You should consult with a legal or tax professional regarding your specific circumstances.